1. H. Amann, Math. Z. 202, 219–250 (1989).
2. Y. Amirat and A. Ziani, J. Math. Anal. Appl. 220, 697–718 (1998).
3. G. Chavent and J. Jaffré, Mathematical Methods and Finite Elements for Reservoir Simulation (North Holland, Amsterdam, 1986).
4. J. Douglas and J. E. Roberts, Math. Comput. 41, 441–459 (1983).
5. Mathematics of Reservoir Simulation: Research Frontiers in Applied Mathematics, Ed. by R.E. Ewing (SIAM, Philadelphia, 1984).