Παραπομπή APA

Gurdeep Raj & Trivedi, P. R. (1998). Environmental biology.

Παραπομπή Chicago Style

Gurdeep Raj και P R. Trivedi. Environmental Biology. New delhi, Akash deep publishing house, 1998.

Παραπομπή MLA

Gurdeep Raj και P R. Trivedi. Environmental Biology. 1998.