What is the book by Kolmogorov? I like his way of teaching mathematics! I found the other books. How do you like A course on higher mathematics: Integral equations and Partial Differential equations by Smirnov? It looks quite long, and I can’t seem to find a copy anywhere… How do you like Mikhailov V. book on PDEs? I am just trying to get a feel for them because I am reading a few others right now.