This image shows the CustomerData__To_Customer.xsl tab in the Oracle JDeveloper. This tab is divided into three columns. The first column contains is labeled as "Source: ReadCust.wsdl", the second column is unlabeled, and the third column is labeled as "Target: USCustomer.wsdl." The first column lists the elements in the ReadCust.wsdl file and the third column lists the elements in the USCustomer.wsdl file. The middle column is empty.