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refer (1)


refer - preprocess bibliographic references for groff


refer [ -benvCPRS ] [ -an ] [ -cfields ] [ -fn ] [ -ifields ]
[ -kfield ] [ -lm,n ] [ -pfilename ] [ -sfields ] [ -tn ]
[ -Bfield.macro ] [ filename... ]


REFER(1)                    General Commands Manual                   REFER(1)

       refer - preprocess bibliographic references for groff

       refer [ -benvCPRS ] [ -an ] [ -cfields ] [ -fn ] [ -ifields ]
             [ -kfield ] [ -lm,n ] [ -pfilename ] [ -sfields ] [ -tn ]
             [ -Bfield.macro ] [ filename... ]

       This  file  documents  the  GNU  version of refer, which is part of the
       groff document formatting system.  refer copies the contents  of  file-
       name... to the standard output, except that lines between .[ and .] are
       interpreted as citations, and lines between .R1 and .R2 are interpreted
       as commands about how citations are to be processed.

       Each citation specifies a reference.  The citation can specify a refer-
       ence that is contained in a bibliographic database by giving a  set  of
       keywords that only that reference contains.  Alternatively it can spec-
       ify a reference by supplying a database record in the citation.  A com-
       bination of these alternatives is also possible.

       For  each  citation,  refer  can produce a mark in the text.  This mark
       consists of some label which can be separated from the  text  and  from
       other labels in various ways.  For each reference it also outputs groff
       commands that can be used by a macro package  to  produce  a  formatted
       reference  for  each  citation.   The output of refer must therefore be
       processed using a suitable macro package.  The -ms and -me  macros  are
       both  suitable.   The  commands to format a citation's reference can be
       output immediately after the citation, or the references may be accumu-
       lated,  and the commands output at some later point.  If the references
       are accumulated, then multiple citations of  the  same  reference  will
       produce a single formatted reference.

       The  interpretation  of  lines between .R1 and .R2 as commands is a new
       feature of GNU refer.  Documents making use of this feature  can  still
       be processed by Unix refer just by adding the lines

              .de R1
              .ig R2
       to  the  beginning  of  the  document.  This will cause troff to ignore
       everything between .R1 and .R2.  The effect of some commands  can  also
       be achieved by options.  These options are supported mainly for compat-
       ibility with Unix refer.  It is usually more  convenient  to  use  com-

       refer  generates  .lf  lines so that filenames and line numbers in mes-
       sages produced by commands that read refer output will be  correct;  it
       also  interprets  lines  beginning  with .lf so that filenames and line
       numbers in the messages and .lf lines that it produces will be accurate
       even if the input has been preprocessed by a command such as soelim(1).

       It is possible to have whitespace between a command line option and its

       Most options are equivalent to commands (for  a  description  of  these
       commands see the Commands subsection):

       -b     no-label-in-text; no-label-in-reference

       -e     accumulate

       -n     no-default-database

       -C     compatible

       -P     move-punctuation

       -S     label "(A.n|Q) ', ' (D.y|D)"; bracket-label " (" ) "; "

       -an    reverse An

              capitalize fields

       -fn    label %n

              search-ignore fields

       -k     label L~%a

              label field~%a

       -l     label A.nD.y%a

       -lm    label A.n+mD.y%a

       -l,n   label A.nD.y-n%a

       -lm,n  label A.n+mD.y-n%a

              database filename

       -sspec sort spec

       -tn    search-truncate n

       These  options  are equivalent to the following commands with the addi-
       tion that the filenames specified on the command line are processed  as
       if  they  were  arguments to the bibliography command instead of in the
       normal way:

       -B     annotate X AP; no-label-in-reference

              annotate field macro; no-label-in-reference

       The following options have no equivalent commands:

       -v     Print the version number.

       -R     Don't recognize lines beginning with .R1/.R2.

   Bibliographic databases
       The bibliographic database is a text file consisting of  records  sepa-
       rated by one or more blank lines.  Within each record fields start with
       a % at the beginning of a line.  Each field has a  one  character  name
       that immediately follows the %.  It is best to use only upper and lower
       case letters for the names of fields.  The name of the field should  be
       followed  by  exactly one space, and then by the contents of the field.
       Empty fields are ignored.  The conventional meaning of each field is as

       %A     The name of an author.  If the name contains a title such as Jr.
              at the end, it should be separated  from  the  last  name  by  a
              comma.   There can be multiple occurrences of the %A field.  The
              order is significant.  It is a good idea always to supply an  %A
              field or a %Q field.

       %B     For an article that is part of a book, the title of the book.

       %C     The place (city) of publication.

       %D     The  date of publication.  The year should be specified in full.
              If the month is specified, the name rather than  the  number  of
              the  month  should be used, but only the first three letters are
              required.  It is a good idea always to supply a %D field; if the
              date  is  unknown,  a  value  such as in press or unknown can be

       %E     For an article that is part of a book, the name of an editor  of
              the  book.  Where the work has editors and no authors, the names
              of the editors should be  given  as  %A  fields  and  , (ed)  or
              , (eds) should be appended to the last author.

       %G     US Government ordering number.

       %I     The publisher (issuer).

       %J     For an article in a journal, the name of the journal.

       %K     Keywords to be used for searching.

       %L     Label.

       %N     Journal issue number.

       %O     Other  information.   This  is usually printed at the end of the

       %P     Page number.  A range of pages can be specified as m-n.

       %Q     The name of the author, if the author is  not  a  person.   This
              will  only be used if there are no %A fields.  There can only be
              one %Q field.

       %R     Technical report number.

       %S     Series name.

       %T     Title.  For an article in a book or journal, this should be  the
              title of the article.

       %V     Volume number of the journal or book.

       %X     Annotation.

       For  all  fields except %A and %E, if there is more than one occurrence
       of a particular field in a record, only the last  such  field  will  be

       If  accent  strings  are  used,  they should follow the character to be
       accented.  This means that the AM macro  must  be  used  with  the  -ms
       macros.   Accent  strings  should  not be quoted: use one \ rather than

       The format of a citation is
              flags keywords

       The opening-text, closing-text and flags components are optional.  Only
       one of the keywords and fields components need be specified.

       The keywords component says to search the bibliographic databases for a
       reference that contains all the words in keywords.  It is an  error  if
       more than one reference if found.

       The fields components specifies additional fields to replace or supple-
       ment those specified in the reference.  When references are being accu-
       mulated and the keywords component is non-empty, then additional fields
       should be specified only on the first occasion that a particular refer-
       ence is cited, and will apply to all citations of that reference.

       The  opening-text  and  closing-text  component specifies strings to be
       used to bracket the label instead  of  the  strings  specified  in  the
       bracket-label command.  If either of these components is non-empty, the
       strings specified in the bracket-label command will not be  used;  this
       behaviour  can  be  altered using the [ and ] flags.  Note that leading
       and trailing spaces are significant for these components.

       The flags component is a list of non-alphanumeric  characters  each  of
       which  modifies  the treatment of this particular citation.  Unix refer
       will treat these flags as part of the keywords and so will ignore  them
       since  they  are  non-alphanumeric.   The following flags are currently

       #      This says to use the label specified by the short-label command,
              instead  of  that  specified  by the label command.  If no short
              label has been specified, the normal label will be used.   Typi-
              cally  the  short label is used with author-date labels and con-
              sists of only the date and possibly a disambiguating letter; the
              # is supposed to be suggestive of a numeric type of label.

       [      Precede  opening-text  with  the  first  string specified in the
              bracket-label command.

       ]      Follow closing-text with the  second  string  specified  in  the
              bracket-label command.

       One  advantages  of  using  the [ and ] flags rather than including the
       brackets in opening-text and closing-text is that you  can  change  the
       style  of  bracket  used  in the document just by changing the bracket-
       label command.  Another advantage is that sorting and merging of  cita-
       tions will not necessarily be inhibited if the flags are used.

       If  a label is to be inserted into the text, it will be attached to the
       line preceding the .[ line.  If there is no such line,  then  an  extra
       line will be inserted before the .[ line and a warning will be given.

       There  is  no special notation for making a citation to multiple refer-
       ences.  Just use a sequence  of  citations,  one  for  each  reference.
       Don't put anything between the citations.  The labels for all the cita-
       tions will be attached to the line preceding the first  citation.   The
       labels  may  also  be  sorted or merged.  See the description of the <>
       label expression, and of the sort-adjacent-labels and abbreviate-label-
       ranges  command.  A label will not be merged if its citation has a non-
       empty opening-text or closing-text.  However, the labels for a citation
       using the ] flag and without any closing-text immediately followed by a
       citation using the [ flag and without any opening-text  may  be  sorted
       and  merged even though the first citation's opening-text or the second
       citation's closing-text is non-empty.  (If you  wish  to  prevent  this
       just make the first citation's closing-text \&.)

       Commands are contained between lines starting with .R1 and .R2.  Recog-
       nition of these lines can be prevented by the -R option.   When  a  .R1
       line is recognized any accumulated references are flushed out.  Neither
       .R1 nor .R2 lines, nor anything between them is output.

       Commands are separated by newlines or ;s.  # introduces a comment  that
       extends  to  the  end  of  the line (but does not conceal the newline).
       Each command is broken up into words.  Words are separated by spaces or
       tabs.  A word that begins with " extends to the next " that is not fol-
       lowed by another ".  If there is no such " the word extends to the  end
       of  the line.  Pairs of " in a word beginning with " collapse to a sin-
       gle ".  Neither # nor ; are recognized inside "s.  A line can  be  con-
       tinued by ending it with \; this works everywhere except after a #.

       Each command name that is marked with * has an associated negative com-
       mand no-name that undoes the effect of name.  For example, the  no-sort
       command  specifies  that references should not be sorted.  The negative
       commands take no arguments.

       In the following description each argument must be a single word; field
       is  used for a single upper or lower case letter naming a field; fields
       is used for a sequence of such letters; m and n are used for a non-neg-
       ative numbers; string is used for an arbitrary string; filename is used
       for the name of a file.

       abbreviate* fields string1 string2 string3 string4
                                Abbreviate the first names of fields.  An ini-
                                tial  letter  will  be  separated from another
                                initial letter by string1, from the last  name
                                by  string2, and from anything else (such as a
                                von or de) by string3.   These  default  to  a
                                period  followed  by a space.  In a hyphenated
                                first name, the initial of the first  part  of
                                the  name will be separated from the hyphen by
                                string4;  this  defaults  to  a  period.    No
                                attempt is made to handle any ambiguities that
                                might result  from  abbreviation.   Names  are
                                abbreviated  before  sorting  and before label

       abbreviate-label-ranges* string
                                Three or more adjacent labels  that  refer  to
                                consecutive  references will be abbreviated to
                                a label consisting of the  first  label,  fol-
                                lowed  by  string  followed by the last label.
                                This is mainly useful with numeric labels.  If
                                string is omitted it defaults to -.

       accumulate*              Accumulate  references  instead of writing out
                                each reference as it is encountered.   Accumu-
                                lated  references will be written out whenever
                                a reference of the form


                                is encountered, after  all  input  files  have
                                been  processed, and whenever .R1 line is rec-

       annotate* field string   field is an annotation; print it at the end of
                                the  reference  as a paragraph preceded by the


                                If string is omitted it will default to AP; if
                                field  is  also  omitted it will default to X.
                                Only one field can be an annotation.

       articles string...       string... are definite or indefinite articles,
                                and  should  be  ignored at the beginning of T
                                fields when sorting.  Initially, the, a and an
                                are recognized as articles.

       bibliography filename... Write  out all the references contained in the
                                bibliographic databases filename...  This com-
                                mand should come last in a .R1/.R2 block.

       bracket-label string1 string2 string3
                                In  the  text, bracket each label with string1
                                and string2.  An occurrence of string2 immedi-
                                ately  followed by string1 will be turned into
                                string3.  The default behaviour is

                                       bracket-label \*([. \*(.] ", "

       capitalize fields        Convert fields to caps and small caps.

       compatible*              Recognize .R1 and .R2 even when followed by  a
                                character other than space or newline.

       database filename...     Search the bibliographic databases filename...
                                For each filename if an index filename.i  cre-
                                ated  by  indxbib(1)  exists,  then it will be
                                searched instead; each index can cover  multi-
                                ple databases.

       date-as-label* string    string  is a label expression that specifies a
                                string with which to replace the D field after
                                constructing the label.  See the Label expres-
                                sions subsection for a  description  of  label
                                expressions.  This command is useful if you do
                                not want  explicit  labels  in  the  reference
                                list, but instead want to handle any necessary
                                disambiguation by qualifying the date in  some
                                way.   The  label used in the text would typi-
                                cally be some combination of  the  author  and
                                date.   In  most cases you should also use the
                                no-label-in-reference command.  For example,

                                       date-as-label D.+yD.y%a*D.-y

                                would attach a disambiguating  letter  to  the
                                year part of the D field in the reference.

       default-database*        The default database should be searched.  This
                                is the default behaviour, so the negative ver-
                                sion  of  this  command is more useful.  refer
                                determines whether the default database should
                                be  searched  on  the  first  occasion that it
                                needs to do a search.  Thus a no-default-data-
                                base  command  must  be  given before then, in
                                order to be effective.

       discard* fields          When the reference is read, fields  should  be
                                discarded;  no  string  definitions for fields
                                will be output.  Initially, fields are XYZ.

       et-al* string m n        Control use of et al in the  evaluation  of  @
                                expressions in label expressions.  If the num-
                                ber of  authors  needed  to  make  the  author
                                sequence unambiguous is u and the total number
                                of authors is t then the last t-u authors will
                                be replaced by string provided that t-u is not
                                less than m and t is not  less  than  n.   The
                                default behaviour is

                                       et-al " et al" 2 3

       include filename         Include filename and interpret the contents as

       join-authors string1 string2 string3
                                This  says  how  authors  should   be   joined
                                together.  When there are exactly two authors,
                                they will be joined with string1.  When  there
                                are  more  than  two authors, all but the last
                                two will be joined with string2, and the  last
                                two  authors  will be joined with string3.  If
                                string3  is  omitted,  it  will   default   to
                                string1;  if  string2  is also omitted it will
                                also default to string1.  For example,

                                       join-authors " and " ", " ", and "

                                will restore the default  method  for  joining

       label-in-reference*      When  outputting  the  reference,  define  the
                                string [F to be the reference's  label.   This
                                is the default behaviour; so the negative ver-
                                sion of this command is more useful.

       label-in-text*           For each reference output a label in the text.
                                The label will be separated from the surround-
                                ing text as  described  in  the  bracket-label
                                command.   This  is  the default behaviour; so
                                the negative version of this command  is  more

       label string             string is a label expression describing how to
                                label each reference.

       separate-label-second-parts string
                                When merging  two-part  labels,  separate  the
                                second part of the second label from the first
                                label with string.  See the description of the
                                <> label expression.

       move-punctuation*        In  the  text, move any punctuation at the end
                                of line past the label.  It is usually a  good
                                idea to give this command unless you are using
                                superscripted numbers as labels.

       reverse* string          Reverse the fields whose names are in  string.
                                Each  field  name  can be followed by a number
                                which says how  many  such  fields  should  be
                                reversed.   If no number is given for a field,
                                all such fields will be reversed.

       search-ignore* fields    While searching  for  keys  in  databases  for
                                which  no index exists, ignore the contents of
                                fields.  Initially, fields XYZ are ignored.

       search-truncate* n       Only require the first n characters of keys to
                                be  given.   In  effect  when  searching for a
                                given key words in the database are  truncated
                                to the maximum of n and the length of the key.
                                Initially n is 6.

       short-label* string      string is a label expression that specifies an
                                alternative  (usually shorter) style of label.
                                This is used when the # flag is given  in  the
                                citation.    When   using   author-date  style
                                labels, the identity of the author or  authors
                                is sometimes clear from the context, and so it
                                may be desirable to omit the author or authors
                                from  the label.  The short-label command will
                                typically be used to specify a label  contain-
                                ing  just a date and possibly a disambiguating

       sort* string             Sort references according to  string.   Refer-
                                ences   will   automatically  be  accumulated.
                                string should be a list of field  names,  each
                                followed  by  a  number,  indicating  how many
                                fields with the name should be used for  sort-
                                ing.   +  can be used to indicate that all the
                                fields with the name should be used.   Also  .
                                can  be used to indicate the references should
                                be sorted using the (tentative)  label.   (The
                                Label  expressions  subsection  describes  the
                                concept of a tentative label.)

       sort-adjacent-labels*    Sort labels that  are  adjacent  in  the  text
                                according  to  their position in the reference
                                list.  This command should usually be given if
                                the  abbreviate-label-ranges  command has been
                                given, or if the label expression  contains  a
                                <>  expression.   This  will  have  no  effect
                                unless references are being accumulated.

   Label expressions
       Label expressions can be evaluated both normally and tentatively.   The
       result  of  normal evaluation is used for output.  The result of tenta-
       tive evaluation, called the tentative label,  is  used  to  gather  the
       information  that  normal  evaluation  needs to disambiguate the label.
       Label expressions specified by the date-as-label and  short-label  com-
       mands  are  not evaluated tentatively.  Normal and tentative evaluation
       are the same for all types of expression other than @, *, and % expres-
       sions.   The  description  below  applies  to normal evaluation, except
       where otherwise specified.

       field n
              The n-th part of field.  If n is omitted, it defaults to 1.

              The characters in string literally.

       @      All the authors joined as specified by the join-authors command.
              The  whole  of each author's name will be used.  However, if the
              references are sorted by author (that is the sort  specification
              starts  with  A+), then authors last names will be used instead,
              provided that this does not introduce  ambiguity,  and  also  an
              initial  subsequence  of  the authors may be used instead of all
              the authors, again provided that this does not introduce ambigu-
              ity.   The use of only the last name for the i-th author of some
              reference is considered to be ambiguous if there is  some  other
              reference, such that the first i-1 authors of the references are
              the same, the i-th authors  are  not  the  same,  but  the  i-th
              authors  last  names are the same.  A proper initial subsequence
              of the sequence of authors for some reference is  considered  to
              be ambiguous if there is a reference with some other sequence of
              authors which also has that subsequence as a proper initial sub-
              sequence.   When  an initial subsequence of authors is used, the
              remaining authors are replaced by the string  specified  by  the
              et-al command; this command may also specify additional require-
              ments that must be met before  an  initial  subsequence  can  be
              used.   @ tentatively evaluates to a canonical representation of
              the authors, such that authors that compare equally for  sorting
              purpose will have the same representation.

       %I     The  serial  number  of the reference formatted according to the
              character following the %.  The serial  number  of  a  reference
              is 1  plus  the number of earlier references with same tentative
              label as this reference.  These expressions tentatively evaluate
              to an empty string.

       expr*  If  there  is another reference with the same tentative label as
              this reference, then expr, otherwise an empty string.  It tenta-
              tively evaluates to an empty string.

       expr-n The  first (+) or last (-) n upper or lower case letters or dig-
              its of expr.  Troff special characters (such as \('a) count as a
              single  letter.   Accent  strings  are retained but do not count
              towards the total.

       expr.l expr converted to lowercase.

       expr.u expr converted to uppercase.

       expr.c expr converted to caps and small caps.

       expr.r expr reversed so that the last name is first.

       expr.a expr with first names abbreviated.  Note that  fields  specified
              in  the abbreviate command are abbreviated before any labels are
              evaluated.  Thus .a is useful only when you want a field  to  be
              abbreviated in a label but not in a reference.

       expr.y The year part of expr.

              The  part  of  expr  before the year, or the whole of expr if it
              does not contain a year.

              The part of expr after the year, or an empty string if expr does
              not contain a year.

       expr.n The last name part of expr.

              expr1  except  that  if the last character of expr1 is - then it
              will be replaced by expr2.

       expr1 expr2
              The concatenation of expr1 and expr2.

              If expr1 is non-empty then expr1 otherwise expr2.

              If expr1 is non-empty then expr2 otherwise an empty string.

              If expr1 is non-empty then expr2 otherwise expr3.

       <expr> The label is in two parts, which are  separated  by  expr.   Two
              adjacent  two-part labels which have the same first part will be
              merged by appending the second part of the second label onto the
              first  label  separated by the string specified in the separate-
              label-second-parts command (initially, a  comma  followed  by  a
              space);  the  resulting label will also be a two-part label with
              the same first part as before merging, and so additional  labels
              can  be  merged  into  it.   Note that it is permissible for the
              first part to be empty; this  maybe  desirable  for  expressions
              used in the short-label command.

       (expr) The same as expr.  Used for grouping.

       The  above  expressions  are  listed  in  order  of precedence (highest
       first); & and | have the same precedence.

   Macro interface
       Each reference starts with a call to the macro ]-.  The string [F  will
       be  defined to be the label for this reference, unless the no-label-in-
       reference command has been given.   There  then  follows  a  series  of
       string  definitions, one for each field: string [X corresponds to field
       X.  The number register [P is set to 1 if the P field contains a  range
       of pages.  The [T, [A and [O number registers are set to 1 according as
       the T, A and O fields end with one of the characters .?!.  The [E  num-
       ber  register  will be set to 1 if the [E string contains more than one
       name.  The reference is followed by a call to the ][ macro.  The  first
       argument to this macro gives a number representing the type of the ref-
       erence.  If a reference contains a J field, it will  be  classified  as
       type 1,  otherwise  if it contains a B field, it will type 3, otherwise
       if it contains a G or R field it will be type 4, otherwise if  contains
       a  I  field it will be type 2, otherwise it will be type 0.  The second
       argument is a symbolic name for the type: other, journal-article, book,
       article-in-book  or  tech-report.   Groups of references that have been
       accumulated or are produced by the bibliography command are preceded by
       a call to the ]< macro and followed by a call to the ]> macro.

       /usr/dict/papers/Ind  Default database.

       file.i                Index files.

       refer  uses  temporary  files.   See  the groff(1) man page for details
       where such files are created.

       REFER  If set, overrides the default database.

       See attributes(7) for descriptions of the following attributes:

       |Availability   | text/groff/groff-core |
       |Stability      | Uncommitted           |

       indxbib(1), lookbib(1), lkbib(1)

       In label expressions, <> expressions are ignored inside  .char  expres-

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       This    software    was    built    from    source     available     at
       https://github.com/oracle/solaris-userland.    The  original  community
       source                was                downloaded                from

       Further information about this software can be found on the open source
       community website at https://www.gnu.org/software/groff.

Groff Version 1.22.3            4 November 2014                       REFER(1)