Judson, S., & Kauffman, M. E. (1990). Physical geology (8th ed.). Prentice Hall.
Chicago Style aipamenaJudson, Sheldon, and Marvin Earl Kauffman. Physical Geology. 8th ed. Englewood Cliffs, N.J.: Prentice Hall, 1990.
MLA aipamenaJudson, Sheldon, and Marvin Earl Kauffman. Physical Geology. 8th ed. Prentice Hall, 1990.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.