एपीए उद्धरण

Chopra, P. (1972). Pricing, distribution, welfare. Kalyani.

शिकागो स्टाइल उद्धरण

Chopra, P.N. Pricing, Distribution, Welfare. Ludhiana: Kalyani, 1972.

एमएलए उद्धरण

Chopra, P.N. Pricing, Distribution, Welfare. Kalyani, 1972.