To create an external identifier, you use an external classification scheme. An external classification scheme has values that are not known to the Registry because the classification scheme has no concepts.
To add an external identifier to an object, search for the appropriate classification scheme, then specify a value.
In the Details area for the object, click the External Identifiers tab.
The External Identifiers table, which can be empty, appears.
A Details Panel window opens.
Type a name and, optionally, a description for the external identifier.
Click the Select ClassificationScheme button.
A ClassificationScheme/Concept Selector window opens.
Expand the ClassificationSchemes node, then select a classification scheme that has no concepts.
Click OK to close the ClassificationScheme/Concept Selector window.
The classification scheme appears in the Details Panel window.
Type a value in the Value field.
Click Add to save the new object and close the Details Panel window.
Click Apply in the Details area for the object.