1. Brown, R. F.: A topological introduction to nonlinear analysis, Second edition, Birkhäuser Boston, Inc., Boston, MA, 2004
2. Deimling, K.: Nonlinear Functional Analysis, Springer-Verlag, Berlin-Heidelberg-New York, 1985
3. Drábek, P., Milota, J.: Lectures on nonlinear analysis, Plzen, Vydavatelský Servis, 2004
4. O’Regan, D., Cho, Y. J., Chen, Y. Q.: Topological degree theory and applications, Series in Mathematical Analysis and Applications, 10, Chapman & Hall/CRC, Boca Raton, FL, 2006
5. Takahashi, W.: Nonlinear functional analysis. Fixed point theory and its applications, Yokohama Publishers, Yokohama, 2000