NILES, N. 0. (1959). Plane trigonometry. Wiley.
Cita Chicago (17th ed.)NILES, Nathan 0. Plane Trigonometry. New York: Wiley, 1959.
Cita MLA (9th ed.)NILES, Nathan 0. Plane Trigonometry. Wiley, 1959.
Atenció: Aquestes cites poden no estar 100% correctes.