APA

Hancock p. l., skimer b. j., . (2000). The Oxford companion to the earth. New York: Oxford university press.

Chicago

Hancock paul l, skimer brian j, . 2000. The Oxford companion to the earth. New York: Oxford university press.

Harvard

Hancock p. l., skimer b. j., . (2000). The Oxford companion to the earth. New York: Oxford university press.

MLA

Hancock paul l, skimer brian j, . The Oxford companion to the earth. New York: Oxford university press. 2000.