HNN extension (English Wikipedia)

Analysis of information sources in references of the Wikipedia article "HNN extension" in English language version.

refsWebsite

Global rank English rank

low place

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doi.org

Higman, Graham; Neumann, Bernhard H.; Neumann, Hanna (1949). "Embedding Theorems for Groups". Journal of the London Mathematical Society. s1-24 (4): 247–254. doi:10.1112/jlms/s1-24.4.247.

upv.es

polipapers.upv.es

Higman, Graham; Neumann, Bernhard H.; Neumann, Hanna (1949). "Embedding Theorems for Groups". Journal of the London Mathematical Society. s1-24 (4): 247–254. doi:10.1112/jlms/s1-24.4.247.