I've used some images on my sites from Wikipedia. Some images are under the 'Creative Commons Attribution-Share Alike 2.0 Generic' license, Creative Commons Attribution 3.0 Unported license, and some are under the GNU license.
As my brain has gone to sleep, whats the best way to write a sentence to 'attribute' the authors of the images to display on my sites?
Thanks for any advice.
If they have a website link to that or otherwise just write Photo courtesy : author's name.
That is what I do if I use photo which are not in public domain.