Meta Data Services Programming
Element References
Nested lists of Extensible Markup Language (XML) elements enable the representation of hierarchical structures of objects. References are used to link objects into a general network of associations. The XML hyperlink mechanism is used to reference objects defined internal to a transfer. An internal object is simply referenced by its transfer identifier (ID).
An object reference is represented by the href attribute of the element tag:
<object_type_name href="#_123"/ >
The object reference indicates the type of the object referred to. To learn the object type, you do not need to navigate the object reference to the target object.