A PDF version is available at https://www.bottomupcs.com/csbu.pdf. A EPUB version is available at https://www.bottomupcs.com/csbu.epub The original souces are available at https://github.com/ianw/bottomupcs This work is licensed under the Creative Commons Attribution-ShareAlike License. To view a copy of this license, visit http://creativecommons.org/licenses/by-sa/3.0/ or send a letter to Creativ