Gaya APA

Petersen, M, S., Rigby, J, K. (1984). Interpreting earth history : a manual in historical geology (Ed. 3). Dubuque, Iowa: WM C. Brown Company Publishers.

Gaya MLA

Petersen, Morris, S.., Rigby, J., Keith. "Interpreting earth history : a manual in historical geology". Ed. 3 Dubuque, Iowa: WM C. Brown Company Publishers, 1984. Text.