APA ציטוט

Spamer, E. E. (1989). The development of geological studies in the Grand Canyon. Philadelphia: Department of Malacology, Academy of Natural Sciences of Philadelphia.

Chicago Style Citation

Spamer, Earle E. The Development of Geological Studies in the Grand Canyon. Philadelphia: Department of Malacology, Academy of Natural Sciences of Philadelphia, 1989.

ציטוט MLA

Spamer, Earle E. The Development of Geological Studies in the Grand Canyon. Philadelphia: Department of Malacology, Academy of Natural Sciences of Philadelphia, 1989.