APA-referens (7:e uppl.)

Open University. Graphs, networks and design. Planarity and colouring. Open University Press.

Chicago-referens (17:e uppl.)

Open University. Graphs, Networks and Design. Planarity and Colouring. Milton Keynes: Open University Press.

MLA-referens (8:e uppl.)

Open University. Graphs, Networks and Design. Planarity and Colouring. Open University Press.

Varning: dessa hänvisningar är inte alltid fullständigt riktiga.