एपीए उद्धरण

Varma,O P. (1973). Economic and regional geography of India. Sterling.

शिकागो स्टाइल उद्धरण

Varma,O P. Economic and Regional Geography of India. New Delhi: Sterling, 1973.

एमएलए उद्धरण

Varma,O P. Economic and Regional Geography of India. Sterling, 1973.