APA

Library of Congress, . (1939). Annual report of the Librarian of Congress for the fiscal year ending. Washington: U.S. G.P.O.

Chicago

Library of Congress, . 1939. Annual report of the Librarian of Congress for the fiscal year ending. Washington: U.S. G.P.O.

Harvard

Library of Congress, . (1939). Annual report of the Librarian of Congress for the fiscal year ending. Washington: U.S. G.P.O.

MLA

Library of Congress, . Annual report of the Librarian of Congress for the fiscal year ending. Washington: U.S. G.P.O. 1939.