TY - CHAP AU - Rodino, L. TI - Gevrey hypoellipticity for a class of operators with multiple characteristics BT - Analytic solutions of partial differential equations - Trento, 1981 AU - Collectif T3 - Astérisque PY - 1981 SP - 249 EP - 262 IS - 89-90 PB - Société mathématique de France UR - http://archive.numdam.org/item/AST_1981__89-90__249_0/ LA - en ID - AST_1981__89-90__249_0 ER -