Cita APA (7th ed.)

Ripley, W. Z. (1907). Railway problems. Ginn.

Cita Chicago (17th ed.)

Ripley, William Z. Railway Problems. Boston: Ginn, 1907.

Cita MLA (8th ed.)

Ripley, William Z. Railway Problems. Ginn, 1907.

Atenció: Aquestes cites poden no estar 100% correctes.