United States. Library of Congress. (1990). Library of Congress classification schedules combined with additions and changes through 1989: Class E-F History : America. Gale Research.
Chicago-referens (17:e uppl.)United States. Library of Congress. Library of Congress Classification Schedules Combined with Additions and Changes Through 1989: Class E-F History : America. Detroit: Gale Research, 1990.
MLA-referens (9:e uppl.)United States. Library of Congress. Library of Congress Classification Schedules Combined with Additions and Changes Through 1989: Class E-F History : America. Gale Research, 1990.
Varning: dessa hänvisningar är inte alltid fullständigt riktiga.