2009/1/14 Sam Johnston samj@samj.net:
It appears that it would be adequate (as a minimum acceptable standard) to specify the CC-BY-SA license and refer to the Wikipedia article - certainly the license section 4(c) allows for significant flexibility in this regard. The attribution itself would then be something like "Wikipedia 'Widgets' article" which is enough in itself for a user to be able to find the article and associated revision history (concise attributions are critical especially for print work, on t-shirts, etc.).
There are a couple of counterpoints to this:
* For pictures, sound files, etc., there is often just a single author. If you are the photographer of a high resolution panorama that you've contributed to Wikipedia, I think it's a reasonable expectation to be named ("Photo by Sam Johnston"), as opposed to being referred to as "Photo from Wikipedia". This is equally true, I think, for articles where there is just a single author, or for pictures which have been subsequently edited a few times.
* The attribution terms should avoid requiring specific reference to Wikipedia, so that it's clear that there is not necessarily a tie between the project in which collaboration currently happens, and any future use of the content. If someone creates a better alternative to Wikipedia where the content is used, why should it be continued to be attributed to Wikipedia, rather than the authors?
I think requiring attribution-by-history should be the best practice for heavily edited articles, at least until we more prominently point out the author credit in the article footer.