This is an expensive book and highly technical. When I first picked it I did not understand anything – even the back cover. However if you want to work with complex NLP expressions (lambda) and work with combinatorial stuff this is a great reference. You will need several years of experience with Lambda expressions, First Order Logic and reasoning to understand the contents of the book. If you are a researcher this is a good investment. If you want to solve a quick problem and move on - I would not recommend this.