Dyfyniad APA

Gilbert, C. M., & Christensen, M. N. j. a. (1967). Physical geology: Laboratory course (2nd ed.). McGraw-HIll.

Dyfyniad Arddull Chicago

Gilbert, Charles Mervin, and Mark N. jt. author Christensen. Physical Geology: Laboratory Course. 2nd ed. New York: McGraw-HIll, 1967.

Dyfyniad MLA

Gilbert, Charles Mervin, and Mark N. jt. author Christensen. Physical Geology: Laboratory Course. 2nd ed. McGraw-HIll, 1967.

Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.