APA stil citiranja
Ore, O. (1967). The four- color problem: The four- color problem. New York: Academic Press.
Chicago stil citiranjaOre, Oystein. The four- color problem: The four- color problem. New York: Academic Press, 1967.
MLA stil citiranjaOre, Oystein. The four- color problem: The four- color problem. New York: Academic Press, 1967.
Napomena: Ova citiranost nije uvijek 100% točna.