Returns the external references of the element
        @rtype: L{CexternalReference}
        @return: the external references (iterator)

def get_external_references(self):
        """
        Returns the external references of the element
        @rtype: L{CexternalReference}
        @return: the external references (iterator)
        """
        node = self.node.find('externalReferences')
        if node is not None:
            ext_refs = CexternalReferences(node)
            for ext_ref in ext_refs:
                yield ext_ref