The very nice
<https://meta.wikimedia.org/wiki/Free_knowledge_based_on_Creative_Commons_licenses>
can also be used as final weapon to smash any remaining doubt about SA.
(Please help translate:
<https://meta.wikimedia.org/w/index.php?title=Special:Translate&group=page-Free+knowledge+based+on+Creative+Commons+licenses&filter=&action=page>.)
Nemo