APA (7th ed.) Citation

Wang, H., & Whittington, D. (2000). Willingness to pay for air quality improvements in Sofia, Bulgaria. World Bank.

Chicago Style (17th ed.) Citation

Wang, Hua, and Dale Whittington. Willingness to Pay for Air Quality Improvements in Sofia, Bulgaria. Washington, D.C: World Bank, 2000.

MLA (9th ed.) Citation

Wang, Hua, and Dale Whittington. Willingness to Pay for Air Quality Improvements in Sofia, Bulgaria. World Bank, 2000.