APA aipamena

Gordon, R. L. (1987). World coal: Economics, policies, and prospects. Cambridge University Press.

Chicago Style aipamena

Gordon, Richard L. World Coal: Economics, Policies, and Prospects. Cambridge [Cambridgeshire]: Cambridge University Press, 1987.

MLA aipamena

Gordon, Richard L. World Coal: Economics, Policies, and Prospects. Cambridge University Press, 1987.