APA-referens (7:e uppl.)

Zerbe, R. O., & Croke, K. (1975). Urban transportation for the environment. Ballinger Publishing Company.

Chicago-referens (17:e uppl.)

Zerbe, Richard O., och Kevin Croke. Urban Transportation for the Environment. Cambridge, Mass: Ballinger Publishing Company, 1975.

MLA-referens (9:e uppl.)

Zerbe, Richard O., och Kevin Croke. Urban Transportation for the Environment. Ballinger Publishing Company, 1975.