Dyfyniad APA

Emmons W. H. William, Thiel G. A. George, Stauffer C. R. Clinton, & Allison I. S Ira. (1939). Geology: Principles and processes. New York, McGraw-Hill Book Company, 1939.

Dyfyniad Arddull Chicago

Emmons W. H. William, Thiel G. A. George, Stauffer C. R. Clinton, and Allison I. S Ira. Geology: Principles and Processes. New York, McGraw-Hill Book Company, 1939, 1939.

Dyfyniad MLA

Emmons W. H. William, et al. Geology: Principles and Processes. New York, McGraw-Hill Book Company, 1939, 1939.

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