I'm posting this to (1) share what I've learned by reading a lot over the last little while, and (2) ask for advice from people that have thought a lot about licensing of books and notes.
I'm looking at different licenses for a Sage-enhanced set of notes, in the spirit of the CCLI grant proposal that was posted here a few days ago (please go read it and make comments! [1] :). I see these notes as incorporating Sage code in examples, like you see in William's number theory book or other tutorials that we've seen in various places. I've spent a while reading up on licenses, and it seems that there are three good possibilities for an "open" license that would allow others to make modifications and freely redistribute the result: 1. GNU Free Documentation License 1.3 2. Creative Commons, Attribution-ShareAlike 3.0 3. plain old GPL GFDL and CC-by-sa are not compatible with GPL, so if I wanted the notes to be distributed with Sage (so the examples turn into doctests, etc.), if I went with (1) or (2), I'd have to dual-license the notes with GPL. However, several organizations have just adopted plain GPL for their documents ([2], maybe Debian too?). GNU does not encourage licensing documents with GPL [3], though. The major difference I see between GFDL and CC-by-sa is that CC-by-sa does not have the requirement that the source be distributed with the work. I like that (I really wish there was a CC-by-sa-src, with that added requirement). However, it seems that there are lots of problems with the GFDL license, not the least of which is the incompatibility with GPL. See [4] or [5]). So what do others do that have written notes that hopefully will eventually be distributed with Sage think? Thanks, Jason [1] http://groups.google.com/group/sage-devel/browse_thread/thread/3e9f66cf3fc3405f# [2] http://en.flossmanuals.net/bin/view/Blog/LicenseChange [3] http://www.gnu.org/licenses/gpl-faq.html#WhyNotGPLForManuals [4] http://web.archive.org/web/20031009105046/http://home.twcny.rr.com/nerode/neroden/fdl.html [5] http://en.wikipedia.org/wiki/GNU_Free_Documentation_License#Criticism -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
