@MartinSleziak the tag group-objects has disappeared because the question has been deleted by the post author. But this tag looked very reasonable to me.
@ToddTrimble The edit to your post was mainly because Asaf Karagila wanted to test some stuff (to see how hiding reputation behaves when something is edited). mathoverflow.net/posts/39388/revisions
I guess that fixing the dead link is useful, whether or not adding the title of the paper is needed is maybe questionable. But it goes without saying that you can revert my second edit, if you prefer.
