APA (7th ed.) Citation

Library of Congress. Union Catalog Division. (1936). Key to symbols used in the Union catalog, Revised edition. [s.n.].

Chicago Style (17th ed.) Citation

Library of Congress. Union Catalog Division. Key to Symbols Used in the Union Catalog, Revised Edition. [Washington]: [s.n.], 1936.

MLA (9th ed.) Citation

Library of Congress. Union Catalog Division. Key to Symbols Used in the Union Catalog, Revised Edition. [s.n.], 1936.