APA (7th ed.) Citation

Knudson, D. M. (1980). Outdoor recreation. MacMillan u.a.

Chicago Style (17th ed.) Citation

Knudson, Douglas M. Outdoor Recreation. New York u.a: MacMillan u.a, 1980.

MLA (9th ed.) Citation

Knudson, Douglas M. Outdoor Recreation. MacMillan u.a, 1980.