- keep the license information
- attribute the original creator ("BY")
- license derived work also under CC-BY-SA (share-alike, "SA").
Wikipedia, one of the web's most popular reference works, switched in mid 2009 to CC-BY-SA. Using the same license as that site makes it easy for this wiki's users to reuse the content from Wikipedia. You must adhere to the CC-BY-SA when using Wikipedia content. See Template:Wikipedia and Template:Wikipedia-text for easy-to use templates for this task.
- License page for version 3.0