Gaya APA

Carlson, D, H., Lummer, C, C. (2008). Physical geologi : Earth revealed (7 th Ed.). Boston: McGraw-Hill Higher Education.

Gaya MLA

Carlson, Diane, H.., Lummer, Charles, C.. "Physical geologi : Earth revealed". 7 th Ed. Boston: McGraw-Hill Higher Education, 2008. Text.