%0 Journal Article %A Lyndon, R.G. %T On the Frouxe-Rabinovitch series for free groups %J Portugaliae mathematica %D 1953 %P 115-118 %V 12 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/PORMA_1953__12_3_114720/ %G en %F PORMA_1953__12_3_114720