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In Pontriaguin's classic book Grupos continuos (in English Continuous Groups), says that A. Markov proved that:

There are topological groups that are not normal.

Furthermore, he says it is deduced from a deeper result of Markov that says:

Every completely regular space can be embedded as a closed subspace of some topological group.

When looking at the references of the book, the article of Markov is cited in russian -which I am unable to transcript-. Nevertheless, a translation to spanish in my copy of the book has in brackets "Sobre grupos topológicos libres", i.e. "On free topological groups". However, I haven't been able to find neither Markov's article (a trasnlation into English) nor any related article to this result.

Does anyone know any reference (in English or Spanish) that exposes this results of Markov?

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Fantastic question. Since I am also curious to see how Markov originally proved his theorem, I tried searching for an English version of the article. This translation definitely exists (but fails to be unique). Here are references that I found in the citations of another paper:

A.A. Markov, On free topological groups, Amer. Math. Soc. Transl. 30 (1950) 11-88; Reprint: Amer. Math. Soc. Transl. 8 (1) (1962) 195-272.

Looking for the translations online has been rather frustrating, since the search dead-ends here: http://www.ams.org/bookstore/trans1series

Meanwhile, there is an overview in the "Handbook of the History of General Topology, Vol 3" with some pages being available on google books here. I quote a tantalizing excerpt here by Michael Tkachenko:

... it turns out that every completely regular space $X$ can be embedded as a closed subspace into a topological group, say $F(X)$. It was A. A. Markov who, in 1941, gave the first construction of such an embedding. The whole construction is quite complicated, the original complete exposition takes about fifty pages...

If you can't find something useful in the handbook, the next thing to do is probably email Michael Tkachenko. Good luck, and please update your question (or post an answer) if you get anywhere. I'm dying to see those "50 pages".

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A simple proof can be found in the book: A. Arhangel'skii, M.Tkachenko: Topological Groups and Related Structures, Atlantis Press 2008 (pp. 81-82)

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