An author has contacted me to use some of my photographs in a book (a big, serious, scholarly, several-volume thing). He contacted me, and several other users, after seeing images on Commons. Consequences:
1) Commons does get some visibility, and provides images to serious work. Cheer up, people !
2) The author is enquiring how I wish to be credited. What do you people think would be a concise yet effective way to mention Wikimedia Commons in such cases ?
Cheers ! -- Rama