Bishop, M. S., & Lewis,Phyllis G. (1972). Focus on earth science (2nd ed.). Charles E. Merrill.
Chicago Style aipamenaBishop, Margaret S., and Lewis,Phyllis G. Focus on Earth Science. 2nd ed. Columbus: Charles E. Merrill, 1972.
MLA aipamenaBishop, Margaret S., and Lewis,Phyllis G. Focus on Earth Science. 2nd ed. Charles E. Merrill, 1972.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.