From the reviews : "This book gives a thorough introduction to several theories that are fundamental to research on modular forms. Most of the material, despite its importance, had previously been unavailable in textbook form. Complete and readable proofs are given... In conclusion, this book is a welcome addition to the literature for the growing number of students and mathematicians in other fields who want to understand the recent developments in the theory of modular forms." # Mathematical Reviews # "This book will certainly be indispensable to all those wishing to get an up-to-date initiation to the theory of modular forms." # Publicationes Mathematicae #
One of the main references in the theory of modular forms that tackles unique topics like modular symbols and period polynomials of Eichler integrals of modular forms of integer weight on the full modular group. The terminology is a bit special and it makes it a bit hard to read for beginners. The book is divided into two parts, modular forms on the full group and modular forms on subgroups of finite index in the full group.