I found project gutenber (http://www.gutenberg.org/ http://www.gutenberg.org/) which has around 53K books and they have this license: http://www.gnu.org/copylef

I found project gutenber (http://www.gutenberg.org/ http://www.gutenberg.org/) which has around 53K books and they have this license: http://www.gnu.org/copyleft/fdl.html http://www.gnu.org/copyleft/fdl.html Which allows commercial use. What do you say in this case?