Gaya APA

Swanson, C, P., Heller, R, L. (1962). Geology and earth sciences sourcebook for elementary and secondary ì schools . New York: New York: Holt, Rinehart and Winston; 1962.

Gaya MLA

Swanson, Carl, P.., Heller, Robert, L. "Geology and earth sciences sourcebook for elementary and secondary ì schools". New York: New York: Holt, Rinehart and Winston; 1962, 1962. Text.