This work is copyrighted, the copyright holder has granted permission for this image to be used. This permission does not extend to third parties.
Copyright holder: Amoka
The text of the permission was: "Hi (sorry, you didn't mention your name) The thing is that I permit to use my art to anyone IF this use is not commercial. So I don't really know about 'distribution' part of the license. If it means 'no commercial use' then go ahead and use these pictures as you want. AFAIK Wikipedia links all images with the source website, so there's no problem there either 8-) Anyway, again - if it's not for commercial use - go ahead and take them, I don't mind at all 8-) Best wishes, Roman Papsuev" 
The original picture can be found on: http://en.amokanet.ru/gallery/martin/
Note that our situation is that we only use images relevant to the TV series, its spin-offs or actors or crew on the wiki, not the books (such images are more properly used on the Wiki of Ice and Fire or the Song of Ice and Fire Wikia). Such images can only be used for user pictures or on someone's profile.