APA استشهاد

Tyagi, A., & Sing, V. UGC NET/SET environment science. Danika.

استشهاد بنمط شيكاغو

Tyagi, Anil, و Virendra Sing. UGC NET/SET Environment Science. 2011: Danika.

MLA استشهاد

Tyagi, Anil, و Virendra Sing. UGC NET/SET Environment Science. Danika.