APA (7th ed.) Citation

Bell, C., & Thomas, T. (1943). Essentials of plane and spherical trigonometry. Henry Holt.

Chicago Style (17th ed.) Citation

Bell, C., and T.Y Thomas. Essentials of Plane and Spherical Trigonometry. New York: Henry Holt, 1943.

MLA (9th ed.) Citation

Bell, C., and T.Y Thomas. Essentials of Plane and Spherical Trigonometry. Henry Holt, 1943.