Mangel AW, Wang J, Sherrill B, Gnanasakthy A, Ervin C, Fehnel SE. Urgency as an endpoint in irritable bowel syndrome. Gastroenterology Research. 2011 Feb 1;4(1):9-12.
Mansfield CA, Johnson FR, Van Houtven GL. The missing piece: valuing averting behavior for children's ozone exposures. Resour Energy Econ. 2006 Aug;28(3):215-28.
Smith VK, Poulos C, Kim H. Treating open space as an urban amenity. Resour Energy Econ. 2002 Feb 15;24(1-2):107-29.