I would consult Paul P. Christensen's excellent work on the former question, such as, for instance: "Historical Roots for Ecological Economics--Biophysical versus Allocative Approaches," In: The development of ecological economics; 85-104; Elgar Reference Collection. International Library of Critical Writings in Economics, vol. 75. Cheltenham, U.K. and Lyme, N.H.: Elgar; distributed by American International Distribution Corporation, Williston, Vt., 1997 [1989]. "Driving Forces, Increasing Returns and Ecological Sustainability," In: Ecological economics: The science and management of sustainability; 75-87; Technical editing by Lisa Wainger, New York: Columbia University Press, 1991. Mathew Forstater