Cita APA

Walters, A. A., & Walters, A. A. (1968). The economics of road user charges. Baltimore, Md.: J. Hopkins.

Citación estilo Chicago

Walters, A. A., y A. A. Walters. The Economics of Road User Charges. Baltimore, Md.: J. Hopkins, 1968.

Cita MLA

Walters, A. A., y A. A. Walters. The Economics of Road User Charges. Baltimore, Md.: J. Hopkins, 1968.