Referencing an Attribute (XML Schema)
It is possible to define an attribute at schema level. This attribute can then be referenced within a tag definition. The purpose is to avoid redundant definitions.
To reference an attribute in the schema editor:
1. Select the attribute in the navigator.
2. In the right part of the editor, select the References tab.
3. Select Referenced attribute and click the Connect button.
4. In the dialog box that opens, find the attribute to be referenced and click OK.