@article{104578, author = {V\'aclav Havel}, title = {Unessential Zassenhaus refinements}, journal = {Archivum Mathematicum}, volume = {001}, year = {1965}, pages = {35-38}, zbl = {0188.04204}, mrnumber = {0194367}, language = {en}, url = {http://dml.mathdoc.fr/item/104578} }
Havel, Václav. Unessential Zassenhaus refinements. Archivum Mathematicum, Tome 001 (1965) pp. 35-38. http://gdmltest.u-ga.fr/item/104578/
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