Cita APA (7th ed.)

United States Library of Congress Classification Division. (1957). Classification. Class P, subclasses P-PM supplement: Index to languages and dialects (2nd ed.). U. S. Government Printing Office.

Cita Chicago (17th ed.)

United States Library of Congress Classification Division. Classification. Class P, Subclasses P-PM Supplement: Index to Languages and Dialects. 2nd ed. Washington: U. S. Government Printing Office, 1957.

Cita MLA (9th ed.)

United States Library of Congress Classification Division. Classification. Class P, Subclasses P-PM Supplement: Index to Languages and Dialects. 2nd ed. U. S. Government Printing Office, 1957.