http://www.loc.gov/mods/v3 http://www.loc.gov/standards/mods/v3/mods-3-2.xsd
combined indexes to the Library of Congress classification schedules, 1974
United States Historical Documents Institute
Set 1. Author-number index. 2 v.--Set 2. Biographical subject index. 2 v.--Set 3. Classified index to persons. 3 v.--Set 4. Geographical name index. 1 v.--Set 5. Subject keyword index. 6 v.