Cita APA (7a ed.)

Werra, D. d., & Hertz, A. (1989). Graph colouring and variations. North-Holland ; Sole distributors for the U.S.A. and Canada, Elsevier Science Pub. Co..

Cita Chicago Style (17a ed.)

Werra, D. de, y A. Hertz. Graph Colouring and Variations. Amsterdam ; New York : New York, N.Y., U.S.A.: North-Holland ; Sole distributors for the U.S.A. and Canada, Elsevier Science Pub. Co., 1989.

Cita MLA (8a ed.)

Werra, D. de, y A. Hertz. Graph Colouring and Variations. North-Holland ; Sole distributors for the U.S.A. and Canada, Elsevier Science Pub. Co., 1989.