APA (7e ed.) Bronvermelding

ZILL, D. G., & DEWAR, J. M. (1990). Trigonometry.-- Ed.2. McGraw-Hill.

Chicago (17e ed.) Bronvermelding

ZILL, Dennis G., en Jacqueline M. DEWAR. Trigonometry.-- Ed.2. New York: McGraw-Hill, 1990.

MLA (9e ed.) Bronvermelding

ZILL, Dennis G., en Jacqueline M. DEWAR. Trigonometry.-- Ed.2. McGraw-Hill, 1990.