There is a book about Deep Learning, http://www.deeplearningbook.org/, which is wrote by Ian Goodfellow, Yoshua Bengio and Aaron Courville.
The Deep Learning textbook is a resource intended to help students and practitioners enter the field of machine learning in general and deep learning in particular. The online version of the book is now complete and will remain available online for free.
Or you can download from my site. But you should bear in mind that you should just use it for research purpose bu not commercial use. If you think i'm infringing, you can contact with me to delete the file.