%0 Journal Article %A Sarkar, Sucharit %T Commutators and squares in free groups %J Algebraic and Geometric Topology %D 2004 %P 595-602 %V 4 %N 1 %U http://geodesic.mathdoc.fr/articles/10.2140/agt.2004.4.595/ %R 10.2140/agt.2004.4.595 %F 10_2140_agt_2004_4_595