TY - JOUR AU - T. Guédénon TI - Projectivity and flatness over the graded ring of semi-coinvariants JO - Algebra and discrete mathematics PY - 2010 SP - 42 EP - 56 VL - 10 IS - 1 PB - mathdoc UR - http://geodesic.mathdoc.fr/item/ADM_2010_10_1_a4/ LA - en ID - ADM_2010_10_1_a4 ER -