%0 Journal Article %A Potrykus, Alexander %T A symbolic calculus and a parametrix construction for pseudodifferential operators with non-smooth negative definite symbols. %J Revista matemática complutense %D 2009 %V 22 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/RMC_2009_2009_1_a13/ %G en %F RMC_2009_2009_1_a13