1. Perturbation Methods;Hinch,1991
2. Introduction to Perturbation Methods;Holmes,1995
3. Methods and Applications of Singular Perturbations: Boundary Layers and Multiple Timescale Dynamics;Verhulst,2005
4. Numerical computation of internal and external flows;Hirsch,1998
5. Numerical Methods for Singularly Perturbed Differential Equations;Roos,2008