APA Citatie

Willis, K. G., Button, K., & Nijkamp, P. (1999). Environmental valuation. Edward Elgar Pub..

Chicago Style citaat

Willis, K. G., Kenneth Button, en Peter Nijkamp. Environmental Valuation. Cheltenham, UK ; Northampton, MA: Edward Elgar Pub., 1999.

MLA citatie

Willis, K. G., et al. Environmental Valuation. Edward Elgar Pub., 1999.