Section 12 GPLv3 states, that you either have to fullfill the conditions of this license conveying your work, or refrain from conveying.
In the following way:
12. No Surrender of Others’ Freedom.
If conditions are imposed on you (whether by court order, agreement or otherwise) that contradict the conditions of this License, they do not excuse you from the conditions of this License. If you cannot convey a covered work so as to satisfy simultaneously your obligations under this License and any other pertinent obligations, then as a consequence you may not convey it at all. For example, if you agree to terms that obligate you to collect a royalty for further conveying from those to whom you convey the Program, the only way you could satisfy both those terms and this License would be to refrain entirely from conveying the Program
(Copyright holder of the license agreement itself is the Free Software Foundation, Inc. <http://fsf.org/> Everyone is permitted by the copyright holder, to copy and distribute verbatim copies of the copyright license document. Changing the copyright-agreement, is not allowed. http://www.gnu.org/licenses/gpl-3.0.en.html.)
Text is modified and available under the Creative Commons Attribution-ShareAlike License; additional terms may apply.
Felix Arndt “The GNU Free Documentation License (GNU FDL or simply GFDL)” 2015; https://mrimagma.wordpress.com/2015/05/27/the-gnu-free-documentation-license-gnu-fdl-or-simply-gfdl/
To share-alike and attribute please use the 2 preceding sentences. Feel free to copy & paste.
MRIMAGMA 