TY - JOUR AU - Deville, Robert AU - Gonzalo, R. AU - Jaramillo Aguado, Jesús Ángel PY - 1999 DO - 10.1017/S0305004198003119 SN - 0305-0041 UR - https://hdl.handle.net/20.500.14352/57600 T2 - Mathematical Proceedings of the Cambridge Philosophical Society AB - We investigate the best order of smoothness of L-p(L-q). We prove in particular that there exists a C-infinity-smooth bump function on L-p(L-q) if and only if p and q are even integers and p is a multiple of q. M2 - 155 PB - Cambridge Univ Press KW - Infinitely smooth bump function TI - Renormings of L-p(L-q) TY - journal article VL - 126 ER -