APA-viite

Fritsch, R., & Fritsch, G. (1998). The four color theorem: History, topological foundations, and idea of proof. Springer.

Chicago-tyylinen lähdeviittaus

Fritsch, Rudolf, ja Gerda Fritsch. The Four Color Theorem: History, Topological Foundations, and Idea of Proof. New York: Springer, 1998.

MLA-viite

Fritsch, Rudolf, ja Gerda Fritsch. The Four Color Theorem: History, Topological Foundations, and Idea of Proof. Springer, 1998.