How do you verify facts claimed by a deceased author? The question is not a arising in my capacity as an academic.  I was recently reading a book, and I came across a claim that seemed dubious; so I wanted to find out whether it was accurate.  I thought of contacting the author, but then I disovered that the author had been dead for a few years.

My question is, what is the appropriate thing to do in such a case, where the author is the only one who has the information necessary to verify a claim, and yet the author is deceased?  Assuming you cared about it enough, would you contact the family of the author, to see if they had notes the author had used in writing the book, or is that impolite?  What else can be done?
Assuming you cared about it enough, would you contact the family of the author, to see if they had notes the author had used in writing the book, or is that impolite?


It's implausible that the author's files are well-organized and clear enough that a non-expert family member could easily answer your question.  And unless the answer is dreadfully important, it seems inappropriate to ask whether you could fly into town and spend hours/days searching through any files the family possesses.  (One can accumulate a large number of boxes of papers over the course of a career.)  That could make sense if you were working on a major project about the author and the family was eager to help, but for an isolated question it feels like far too much of an imposition on the family.

If the family felt the files were likely to be of continuing academic or historical interest, then they may have donated them to a university library or archive (most likely at the university the author worked at, if any).  I'd start by doing web searches to try to find out.  If you can't find out online, you could enquire at the most likely university library.

Before trying to track down the author's files, it's worth convincing yourself that there's no other way to get an answer.  For example, maybe the author is alluding to something well known among a certain community, or maybe the author supplied more details in a different publication.  You could try ask online (e.g., on a suitable stack exchange site) and see what happens.

If the author worked with a collaborator or had a student who specialized in this topic, then they would be natural people to ask.  You could also try asking another expert (e-mailing someone out of the blue will come across best if you give an explanation of how you have tried and failed to find the answer).

If nobody else knows and the author's files weren't formally archived anywhere, then I'm not sure how much more you can do.  The author's information may simply be lost and will have to be reconstructed from scratch.