Here is your reminder to always use really free books sources ( Cretive Commons or Public domain) and to donate to them.

Maybe one day, we will be more open about knowledge sharing.

Sources to read free books:

• Unglue.it.
• Wikibooks.
• The Center for the Book in the Library of Congress.
• Authorama.
• Europeana.
• Wikisource.
• IntechOpen.
• Project Gutenberg.
• DOAB search engine.