APA (7th ed.) Citation

Ringel, G. (1974). Map color theorem. Springer-Verlag.

Chicago Style (17th ed.) Citation

Ringel, Gerhard. Map Color Theorem. Berlín: Springer-Verlag, 1974.

MLA (9th ed.) Citation

Ringel, Gerhard. Map Color Theorem. Springer-Verlag, 1974.