1. Abramowitz, M., Stegun, I.A.: Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables. NIST, Gaithersburg (1964)
2. Alexander, J., Gardner, R., Jones, C.: A topological invariant arising in the stability analysis of travelling waves. J. Reine Angew. Math. 410, 167–212 (1990)
3. Proc. Sympos. Pure Math.;H. Brezis,1999
4. Brézis, H., Nirenberg, L.: Positive solutions of nonlinear elliptic equations involving critical Sobolev exponents. Commun. Pure Appl. Math. 36, 437–477 (1983)
5. Brunovský, P.: C r -inclination theorems for singularly perturbed equations. J. Differ. Equ. 155, 133–152 (1999)