TY - JOUR AU - Imre Ruzsa TI - A concavity property for the measure of product sets in groups JO - Fundamenta Mathematicae PY - 1991 SP - 247 EP - 254 VL - 140 IS - 3 PB - mathdoc UR - http://geodesic.mathdoc.fr/articles/10.4064/fm-140-3-247-254/ DO - 10.4064/fm-140-3-247-254 LA - en ID - 10_4064_fm_140_3_247_254 ER -