E. A.  Machado, Stoms, D. M., Davis, F. W., and Kreitler, J., ?Prioritizing farmland preservation cost-effectively for multiple objectives?, Journal of Soil and Water Conservation, vol. 61, pp. 250-258, 2006.

D. M.  Stoms and Davis, F. W., ?Defining a marginal value function for setting conservation priorities in NatureServe Vista?, University of California Santa Barbara, 2005.