1. Nonlinear Superposition Operators;Appell,1990
2. An Introduction to Nonlinear Boundary Value Problems;Bernfeld,1974
3. A. Cabada, J.A. Cid, R.L. Pouso, Positive solutions for a class of singular differential equations arising in diffusion processes, Dynamics Continuous Discrete Impuls. Systems, to appear.
4. Extremality results for discontinuous explicit and implicit diffusion problems;Cabada;J. Comput. Appl. Math.,2002
5. Approximate solutions to a new class of nonlinear diffusion problems;Cabada;J. Comput. Appl. Math.,1999