This work is licensed under the Creative Commons Attribution-ShareAlike License. To view a copy of this license, see the file license.txt, visit http://creativecommons.org/licenses/by-sa/2.0 or send a letter to Creative Commons, 559 Nathan Abbott Way, Stanford, California 94305, USA. This component schema defines the XML Schema content model groups customElements and customAttributes to support validation of extension XML elements and attributes. This component XSD should be used if extensions are to be supported in LOM XML instances.