APA
Negi S. S., . (2008). A hand book of environmental science. Dehra Dun: Bishen Singh Mahendra Pal Singh.
Chicago
Negi S S, . 2008. A hand book of environmental science. Dehra Dun: Bishen Singh Mahendra Pal Singh.
Harvard
Negi S. S., . (2008). A hand book of environmental science. Dehra Dun: Bishen Singh Mahendra Pal Singh.
MLA
Negi S S, . A hand book of environmental science. Dehra Dun: Bishen Singh Mahendra Pal Singh. 2008.