Board Thread:The Reference Desk/@comment-24894325-20160604220557/@comment-24894325-20160731145911

The reason I am asking is because the language of T:DAB only talks about appearances and there is a forum thread discussing what constitute an appearance. This is why I thought this is not a trivial matter. I think it was discussed at some point that Empress Elisabeth should not be called "Sisi (The Silver Turk)" because she never actually appears in the story, she is just mentioned by the characters. So I feel that there must be a more nuanced rule, perhaps, distinguishing characters only mentioned in one story from characters from the real universe and characters mentioned in many stories but not occurring in any of them.