1. Introduction to Perturbation Techniques;Nayfeh,1993
2. Singular Perturbation Methods for Ordinary Differential Equations;O’Malley,1991
3. Uniform Numerical Methods for Problems with Initial and Boundary Layers;Doolan,1980
4. Fitted Numerical Methods for Singular Perturbation Problems;Miller,1996
5. Numerical Methods for Singularly Perturbed Differential Equations;Roos,1996