United States. Library of Congress. (1990). Library of Congress classification schedules combined with additions and changes through 1989: Class D history : General and Old world. Gale Research.
Chicago Style aipamenaUnited States. Library of Congress. Library of Congress Classification Schedules Combined with Additions and Changes Through 1989: Class D History : General and Old World. Detroit: Gale Research, 1990.
MLA aipamenaUnited States. Library of Congress. Library of Congress Classification Schedules Combined with Additions and Changes Through 1989: Class D History : General and Old World. Gale Research, 1990.
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