On normalized Laplacian eigenvalues of graphs

This is a book about the normalized Laplacian eigenvalues of a graph, which contains the research results during my Ph.D study in Sungkyunkwan University, Suwon, Korea. The normalized Laplacian eigenvalues of a graph contain many useful information of the graph, which eigenvalues of other matrices are failed to do. Thus, I want to share these results with others and this book may help you to have more ideas on this topic. Moreover, several open problems are also given, which can be considered for further research.