Franklin

MLA

Hancock, Paul L, and Brian J Skinner. Oxford Companion to the Earth. Oxford: Oxford University Press, 2000.

APA

Hancock, P. L, & Skinner, B. J. (2000). Oxford companion to the earth. Oxford: Oxford University Press.

Chicago

Hancock, Paul L., and Brian J. Skinner. Oxford Companion to the Earth. Oxford: Oxford University Press, 2000.