[1] Dale M Heien and Cathy Roheim Wessels, “The Demand for Dairy Products: Structure, Prediction, and Decomposition,” American Journal of Agricultural Economics 70:2 (May 1988): 219–228 [2] David Romer, “Do Students Go to Class? Should They?” Journal of Economic Perspectives 7:3 (Summer 1993): 167–174 Attributed to Libby Rittenberg and Timothy Tregarthen Saylor URL: http://www.saylor.org/books/ Saylor.org 289