TY - JOUR AU - Mauceri, Giancarlo TI - Riesz means for the eigenfunction expansions for a class of hypo-elliptic differential operators JO - Annales de l'Institut Fourier PY - 1981 DA - 1981/// SP - 115 EP - 140 VL - 31 IS - 4 PB - Institut Fourier UR - http://archive.numdam.org/articles/10.5802/aif.851/ UR - https://zbmath.org/?q=an%3A0455.35039 UR - https://www.ams.org/mathscinet-getitem?mr=84h:35125 UR - https://doi.org/10.5802/aif.851 DO - 10.5802/aif.851 LA - en ID - AIF_1981__31_4_115_0 ER -