Natural resource economics : notes and problems / Conrad, Jon M. Clark, Colin Whitcomb, Natural resources. Environmental policy. 333 CAM 1987 A075 Or. Includes index. Cambridge [Cambridgeshire] ; New York : Cambridge University Press, 1987. 1987. Text x, 231 p. : http://www.loc.gov/catdir/samples/cam034/87011582.html http://www.loc.gov/catdir/description/cam023/87011582.html http://www.loc.gov/catdir/toc/cam025/87011582.html