Hudson, R. G. The engineers' manual (second.). 1917, 1939.
Cita Chicago (17th ed.)Hudson, Ralph Gorton. The Engineers' Manual. second. 1917, 1939.
Cita MLA (9th ed.)Hudson, Ralph Gorton. The Engineers' Manual. second. 1917, 1939.
Atenció: Aquestes cites poden no estar 100% correctes.