For this edition, a number of typographical errors and minor slip-ups have been corrected. In addition, following the persistent encouragement of Olga Oleinik,

... The progress of physics will to a large extent depend on the progress of nonlinear mathe matics, of methods to solve nonlinear equations ... and therefore w

Why writing a book about a specialized task of the large topic of complex systems? And who will read it? The answer is simple: The fascination for a didacticall

Although the book is largely self-contained, some knowledge of the mathematics of differential equations is necessary. Thus the book is intended for mathematici