APA
Richards O.W, . (1997). Imms General Textbook of entomology vol 2 Classificaion & Biology. : B.I. Publication Pvt. Ltd, New Delhi.
Chicago
Richards O.W, . 1997. Imms General Textbook of entomology vol 2 Classificaion & Biology. : B.I. Publication Pvt. Ltd, New Delhi.
Harvard
Richards O.W, . (1997). Imms General Textbook of entomology vol 2 Classificaion & Biology. : B.I. Publication Pvt. Ltd, New Delhi.
MLA
Richards O.W, . Imms General Textbook of entomology vol 2 Classificaion & Biology. : B.I. Publication Pvt. Ltd, New Delhi. 1997.