XPointer, XML Pointer Language

From the dataset abstract

This specification defines the XML Pointer Language (XPointer), the language to be used as the basis for a fragment identifier for any URI reference that locates a resource whose Internet media type is one of text/xml, application/xml, text/xml-external-parsed-entity, or application/xml-external-parsed-entity. (31.08.2011)

Source: XPointer, XML Pointer Language