5Learning Technology Standards Committee of the Institute of Electrical and Electronics Engineers, Inc., 1484.12.1, Draft Standard for Learning Object Metadata, July 15, 2002.
6IMS Global Learning Consortium, Inc., IMS Content Packaging Information Model Version 1.1.2 Final Specification, August 8, 2001.
7IMS Global Learning Consortium. Inc., IMS Question and Test Interoperability Information Model Version 2.0 Final Specification, January 24, 2005.
8List of Dewey Decimal classes], http://en.wikipedia.org/wiki/ List_ of_Dewey_Decimal_classes.
9Library of Congress.United States, Library of Congress Classification, http://www.loc.gov/catdir/epso/lcco/.
10Outline of the UDC, UDC Consortium, http://www.udcc.org/outline/ outline.htm.