David Hurtubise

This book became available during my last year in graduate school. I bought this book when it was first published, and it has remained one of my essential references for the past ten years. It is one of the few books on differential topology that contains rigorous proofs that do not rely on the phrases "it can be shown that" and "it is obvious that". The exposition in this book is clear and precise from the beginning to the end. It also contains a lot of historical remarks and comments that are quite interesting.