United States. Library of Congress. (1990). Library of Congress classification schedules combined with additions and changes through 1989: Class T Technology. Gale Research.
Chicago-Zitierstil (17. Ausg.)United States. Library of Congress. Library of Congress Classification Schedules Combined with Additions and Changes Through 1989: Class T Technology. Detroit: Gale Research, 1990.
MLA-Zitierstil (9. Ausg.)United States. Library of Congress. Library of Congress Classification Schedules Combined with Additions and Changes Through 1989: Class T Technology. Gale Research, 1990.
Achtung: Diese Zitate sind unter Umständen nicht zu 100% korrekt.