Dyfyniad APA

Hedley, D. (1981). World energy: The facts and the future. New York: Facts on File.

Dyfyniad Arddull Chicago

Hedley, Don. World Energy: The Facts and the Future. New York: Facts on File, 1981.

Dyfyniad MLA

Hedley, Don. World Energy: The Facts and the Future. New York: Facts on File, 1981.

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