Gaya APA

CROWDIS, D, G., Wheeler, B, W. (1971). TRIGONOMETRY : A FUNCTIONAL APPROACH . United States of America.: McGRAW-HILL.

Gaya MLA

CROWDIS, David, G.., Wheeler, Brandon, W.. "TRIGONOMETRY : A FUNCTIONAL APPROACH". United States of America.: McGRAW-HILL, 1971. Textbook.