APA (7th ed.) Citation

Library of Congress. Research Services. (1930). L.C. classification, additions and changes. [publisher not identified].

Chicago Style (17th ed.) Citation

Library of Congress. Research Services. L.C. Classification, Additions and Changes. [Washington]: [publisher not identified], 1930.

MLA (9th ed.) Citation

Library of Congress. Research Services. L.C. Classification, Additions and Changes. [publisher not identified], 1930.