If I would like to credit someone for helping out via an answer they gave (i.e., in the "thanks" section in a published book), what is the best way to ask for their real name? Because there is no private message feature on Stack Exchange, I can't think of a way to ask for real name that does not require them making it public (on the question page).
My going-in idea is just to ask for the real name as a comment to their answer, explaining why. If they are willing to provide it in the comments, fine, otherwise I guess I will have to thank them by userid, or not thank them at all.