Smith, K. J. (1987). Trigonometry for college students (4th ed.). Brooks/Cole Pub. Co..
Cita Chicago (17th ed.)Smith, Karl J. Trigonometry for College Students. 4th ed. Monterey, Calif.: Brooks/Cole Pub. Co., 1987.
Cita MLA (9th ed.)Smith, Karl J. Trigonometry for College Students. 4th ed. Brooks/Cole Pub. Co., 1987.
Atenció: Aquestes cites poden no estar 100% correctes.