Gaya APA

Droyan, I., Hadel, W. (1967). Trigonometry; An analytic approach (1967). : USA : The Macmillan Co.,.

Gaya MLA

Droyan, I., Hadel, W. "Trigonometry; An analytic approach". 1967 : USA : The Macmillan Co.,, 1967. Text.