If you're really troubled by this you should just ask the OP why they hadn't included the author's name from the start. This is probably a more diplomatic approach than editing someone else's post.
]]>@Francois: The OP himself mentioned Waterhouse as an answer... in the comments. I don't feel like rolling back my edit right now as it seems that my notions of etiquette and its importance aren't exactly the common opinion here, but if more people confirm that naming the author is completely unproblematic, I'll do so.
]]>The question asks for a clarification, which is the right way to formulate these questions. If, after careful analysis, it turns out to be an error then an answer should point that out. If there is some way to fix the error, then that should be explained too. The only special etiquette rule for errata is to never make unfounded claims.
]]>http://mathoverflow.net/questions/83241
The OP wanted clarification on a result in Waterhouse's book that seemed wrong to him (and seems wrong to me, but I haven't read the proof - most likely it is really just bad notation). At the same time he probably didn't want to spoil the google hits for the author's name. So he only mentioned the name of the book, but not the author. Commenters were confused and I decided to edit the author's name in (I am 99.9% sure it is the right one, the section number matches). He removed it again. Is this a case of etiquette versus readability?
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