A note on topological groups
Compositio Mathematica, Volume 3 (1936), p. 427-430 
@article{CM_1936__3__427_0,
     author = {Birkhoff, Garrett},
     title = {A note on topological groups},
     journal = {Compositio Mathematica},
     publisher = {Johnson Reprint Corporation},
     volume = {3},
     year = {1936},
     pages = {427-430},
     zbl = {0015.00702},
     language = {en},
     url = {http://www.numdam.org/item/CM_1936__3__427_0}
}

Birkhoff, Garrett. A note on topological groups. Compositio Mathematica, Volume 3 (1936) pp. 427-430. http://www.numdam.org/item/CM_1936__3__427_0/

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