Cita APA (7th ed.)

Zappe, R. W. (1981). Valve selection handbook. Gulf.

Cita Chicago (17th ed.)

Zappe, R. W. Valve Selection Handbook. Houston: Gulf, 1981.

Cita MLA (9th ed.)

Zappe, R. W. Valve Selection Handbook. Gulf, 1981.

Atenció: Aquestes cites poden no estar 100% correctes.