by Allen B. Downey
How to Think... is a free textbook available under the GNU Free Documentation License. Permission is granted to copy, distribute, and/or modify this document under the terms of the GNU Free Documentation License, Version 1.1 or any later version published by the Free Software Foundation; with Invariant Sections being "Preface", with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the appendix entitled "GNU Free Documentation License."
Publisher: Green Tea Press
Copyright 2003 Allen Downey