The page used to claim that the Hurewicz theorem is due to (after reformatting):

- Witold Hurewicz:
*Beiträge zur Topologie der Deformationen (I. Höherdimensionale Homotopiegruppen)*, Proc. Akad. Wet. Amsterdam**38**(1935) 112–119 [pdf]

but I suppose it is really due to part II:

- Witold Hurewicz:
*Beiträge zur Topologie der Deformationen (II. Homotopie- und Homologigruppen)*, Proc. Akad. Wet. Amsterdam**38**(1935) 521–528 [pdf]

I have fixed this here and instead am adding pointer to part I above at *homotopy group*.

ah, great, thanks!

I have also updated the link here

]]>Added a direct link for the official digitized PDF of Hurewicz’s paper in the open digital archive of Indagationes Mathematicae.

]]>Okay, sounds good.

Sure, GoogleBooks rarely shows content these days, but in the absence of any published page for a reference, it is at least a kind of online proof of existence.

(Incidentally, some GBooks look inaccessible but do still open up as soon as one uses the “search inside” functionality. Not though in this case, unfortunately.)

]]>Re #9: I think supplying the book name is sufficient, which is what I just did. Everybody knows where to look for books these days. These Google Books links are now quite useless, by the way: it is virtually impossible to look inside. (This used to be quite different 10 years ago or so.)

]]>Added:

This article is reproduced on pages 341–348 of

- Collected Works of Witold Hurewicz. (Edited by Krystyna Kuperberg.) American Mathematical Society, 1995. ISBN 0-8218-0011-6

I noticed that the section stating the actual theorem (here) did not mention the cases in degree $\leq 1$. I have now filled that in by essentially copying over the two Propositions to this extent that we did have all along at *singular homology*.

Also added a kind of Idea-paragraph to before these statements (still here)

]]>Right, I should have been more explicit: I am looking for useful hyperlinks that we could provide with the reference item on the nLab page. I guess we dont want to link to Library Genesis from nLab pages to avoid legal trouble.(?) At least thats what I used to not do.

]]>Re #7: The article is reproduced in its entirety in “Collected Works of Witold Hurewicz”, a book that is available online in Library Genesis.

Here is a full citation:

Koninklijke Akademie van Wetenschappen: Proceedings of the Section of Sciences 38 (1935), 112–119.

Mathematics. — Beiträge zur Topologie der Deformationen (l. Höherdimensionale Homotopiegruppen).

By Dr. W. Hurewicz

(Communicated by Prof. L. E. J. Brouwer).

]]>thanks. is there any online trace of *Beiträge zur Topologie der Deformationen*? I only see it listed on gbooks, where however no content is visible either

Added:

The original reference is

- Witold Hurewicz, _Beitrage zur Topologie der Deformationen), Neder. Akad. Wetensch. 38 (1935), 521–528.

The simplicial version is due to

- Daniel M. Kan,
*The Hurewicz theorem*, 1958 Symposium internacional de topología algebraica (International symposium on algebraic topology), pp. 225–231 Universidad Nacional Autónoma de México and UNESCO, Mexico City.

added paragraph (here) indicating the stable version and its generalization to the *Boardman homomorphism*

added to *Hurewicz theorem* the definition of the *Hurewicz homomorphism*.

noticed that *Hurewicz theorem* was still empty, and briefly added the statement

I have created several entries today, under construction, and will report more on that in few days, when having time, some are such stubs and some have some real material like Selberg integral.

]]>created placeholder for Hurewicz theorem

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