For Wikimedia Content: Copy the CC license from the image page to include in the attribution as it includes a link to the appropriate license.
Format
Author’s name, ‘Title of work’,
http://www.originalsourcelink, accessed dd/mm/yy
Available under a Creative Commons 2.0 Attribution licence:
http://creativecommons.org/licenses/by/2.0/deed.en
Example Markup
<div class="thumbnail with-caption"> <img alt="Image of a stream" class="img-responsive" src="image.jpg" /> <small>Image of a stream" title="Author's name, 'Title of work', http://www.originalsourcelink, accessed dd/mm/yy, Available under a Creative Commons 2.0 Attribution licence: http://creativecommons.org/licenses/by/2.0/deed.en</small> </div>
Example
Author's Name, ‘Title of work’,
http://www.originalsourcelink, accessed dd/mm/yy,
Available under a Creative Commons 2.0 Attribution licence: http://creativecommons.org/licenses/by/2.0/deed.en