Cita APA (7th ed.)

(1973). Classification - class A: General works. Washington, D C : Library of Congress.

Cita Chicago (17th ed.)

Classification - Class A: General Works. Washington, D C : Library of Congress, 1973.

Cita MLA (9th ed.)

Classification - Class A: General Works. Washington, D C : Library of Congress, 1973.

Atenció: Aquestes cites poden no estar 100% correctes.