APA (7th ed.) Citation

Pennak, R. W. (1978). Fresh-water invertebrates of the United States (2d ed.). Wiley.

Chicago Style (17th ed.) Citation

Pennak, Robert W. Fresh-water Invertebrates of the United States. 2d ed. New York: Wiley, 1978.

MLA (9th ed.) Citation

Pennak, Robert W. Fresh-water Invertebrates of the United States. 2d ed. Wiley, 1978.

Warning: These citations may not always be 100% accurate.