1. The references listed below have been chosen from published articles that contain the three elements of theory, documented program codes or model construction features, and applications . Articles that do not have these three elements are somewhat limited in scope and have been purposely avoided.
2. The type of model described in the reports is listed immediately following the citation.
3. This reference list would make a small library which would represent the state-of-the-art in ground-water modeling from a practical viewpoint.
4. C. R. Amerman, 1976 . Waterflow in soils: A generalized steady-state, two-dimensional porous media flow model . Agricultural Research Service, U.S. Department 'of Agriculture Report ARS-NC-30, 62 pp. (Finite difference).