एपीए उद्धरण

Purdom, P. W. (1983). Environmental science: Managing the environmental. Columbus: Merrill.

शिकागो स्टाइल उद्धरण

Purdom, P. Walton. Environmental Science: Managing the Environmental. Columbus: Merrill, 1983.

एमएलए उद्धरण

Purdom, P. Walton. Environmental Science: Managing the Environmental. Columbus: Merrill, 1983.