http://creativecommons.org/licenses/by-sa/1.0/
http://creativecommons.org/licenses/by-sa/1.0/legalcode
Attribution-
ShareAlike 1.0
by
Attribution. The licensor permits others to copy, distribute, display, and perform the work. In return, licensees must give the original author credit.
sa
Share Alike. The licensor permits others to distribute derivative works only under a license identical to the one that governs the licensor's work.
voir
CreativeCommons