This is a simple bibliographic request that I have been unable to pin down. Max Dehn's solution to Hilbert's 3rd problem is: > Max Dehn, "Über den Rauminhalt." _Mathematische Annalen_ <b>55</b> (190x), no. 3, pages 465–478. It is variously cited as either 1901 or 1902 (but always volume 55; Hilbert's own footnote cites volume 55 "soon to appear"). E.g., * [Mathworld][1] cites it as 1902. * The [Encyclopedic Dictionary of Mathematics][2] cites it as 1902. * [Wikipedia][3] says 1901. * Various papers, e.g., [this one][4], and [Tao's book][5], cite it as 1901. I have been unsuccessful in finding the definitive year via the web, because of all the conflicting citations. The next step is to retrieve _Mathematische Annalen_ volume 55, but perhaps someone can spare me that trouble...? Thanks! [1]: http://mathworld.wolfram.com/DehnInvariant.html [2]: http://books.google.com/books?id=WHjO9K6xEm4C&pg=PA613&lpg=PA613&dq=%2522%25C3%259Cber+den+Rauminhalt.%2522+Math.+Ann.+55,+465-478,+1902.&source=bl&ots=wbRTx7whWt&sig=qKQh4tITFtoBltGTIFKZIsphIw4&hl=en&ei=SYlWTqfSOMXbgQfoptWbDA&sa=X&oi=book_result&ct=result&resnum=5&ved=0CEEQ6AEwBA#v=onepage&q&f=false [3]: http://en.wikipedia.org/wiki/Hilbert%2527s_third_problem [4]: http://arxiv.org/abs/math/9712226 [5]: http://www.scribd.com/doc/57582107/12/Bibliography