@article{GDZPPN002401576, title = {On Some Varieties of Soluble Groups. II.}, journal = {Mathematische Zeitschrift}, volume = {105}, year = {1968}, pages = {162-172}, zbl = {0155.04502}, url = {http://dml.mathdoc.fr/item/GDZPPN002401576} }
Levin, Frank. On Some Varieties of Soluble Groups. II.. Mathematische Zeitschrift, Tome 105 (1968) pp. 162-172. http://gdmltest.u-ga.fr/item/GDZPPN002401576/