Proofs of "Table of Integrals, Series, and Products" formulas http://www.amazon.com/Integrals-Series-Products-Seventh-Edition/dp/0123736374
This book is amazing. But there are no proofs in it. Is there book or site which contains all of the proofs of this book's formulas?
 A: From the Wikipedia article for Gradshteyn and Ryzhik:

Victor Hugo Moll with George Boros started a project to prove all integrals listed in Gradshteyn and Ryzhik and add additional commentary and references. In the foreword of the book Irresistible Integrals (2004), they wrote:

It took a short time to realize that this task was monumental.



Nevertheless, the efforts have meanwhile resulted in about 900 entries from Gradshteyn and Ryzhik discussed in a series of more than 30 articles of which papers 1 to 28 have been published in issues 14 to 26 of Scientia, Universidad Técnica Federico Santa María (UTFSM), between 2007 and 2015 and compiled into a two-volume book series Special Integrals of Gradshteyn and Ryzhik: the Proofs (2014–2015) already.

The two volume work can be purchased on amazon: volume 1 and volume 2. I've been tempted to get it myself, the proofs are probably more valuable than the formulae themselves to those interested in preserving mathematical knowledge, and they're probably more useful to anyone able to dedicate the time studying them.
