《国外数学名著系列(续1)(影印版)50:动力系统4(分歧理论和突变理论)》主要内容：Both bifurcation theory and catastrophe theory are studies of smooth systems，tbcusing on properties that seem manifestly non-smooth. Bifurcations are sudden changes that occur in a system as one or more parameters are varied.Catastrophe theory is accurately described as singularity theory and its applications.

These two theories are important tools in the study of differential equations and of related physical systems.Analyzing the bifurcations or singularities of a system provides useful qualitative information about its behaviour. The authors have written this book with reffeshing clarity.Theexposition is masterful，with penetrating insights.