एपीए उद्धरण

Cassels, J. (1960). How to sell successfully by direct mail. Business publications.

शिकागो स्टाइल उद्धरण

Cassels, J.W.W. How to Sell Successfully by Direct Mail. London: Business publications, 1960.

एमएलए उद्धरण

Cassels, J.W.W. How to Sell Successfully by Direct Mail. Business publications, 1960.