APA (7th ed.) Citation

U.S. Library of Congress. Music Division, Sonneck, O. G. T., & Schatz, A. (1914). Catalogue of opera librettos printed before 1800. Govt. Print. Off.

Chicago Style (17th ed.) Citation

U.S. Library of Congress. Music Division, Oscar George Theodore Sonneck, and Albert Schatz. Catalogue of Opera Librettos Printed Before 1800. Washington: Govt. Print. Off, 1914.

MLA (9th ed.) Citation

U.S. Library of Congress. Music Division, et al. Catalogue of Opera Librettos Printed Before 1800. Govt. Print. Off, 1914.