APA (7th ed.) Citation

Library of Congress. (1930). Exhibit of books printed during the XV century and known as incunabula. U.S. Govt. print. off..

Chicago Style (17th ed.) Citation

Library of Congress. Exhibit of Books Printed During the XV Century and Known as Incunabula. Washington: U.S. Govt. print. off., 1930.

MLA (8th ed.) Citation

Library of Congress. Exhibit of Books Printed During the XV Century and Known as Incunabula. U.S. Govt. print. off., 1930.