APA

Emmons R. C., . (1943). The universal stage. New York: Geol.Soc.of America.

Chicago

Emmons R C, . 1943. The universal stage. New York: Geol.Soc.of America.

Harvard

Emmons R. C., . (1943). The universal stage. New York: Geol.Soc.of America.

MLA

Emmons R C, . The universal stage. New York: Geol.Soc.of America. 1943.