Bell, F. G. (2007). Engineering geology (2nd ed.). Elsevier.
Chicago Style aipamenaBell, F. G. Engineering Geology. 2nd ed. Amsterdam: Elsevier, 2007.
MLA aipamenaBell, F. G. Engineering Geology. 2nd ed. Elsevier, 2007.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.