APA استشهاد

Duggal, K. N. (1983). Elements of public health engineering (3rd.). S. Chand.

استشهاد بنمط شيكاغو

Duggal, K. N. Elements of Public Health Engineering. 3rd. New Delhi: S. Chand, 1983.

MLA استشهاد

Duggal, K. N. Elements of Public Health Engineering. 3rd. S. Chand, 1983.