@article{GDZPPN002431300,
title = {Commutator Methods and a Smoothing Property of the Schr\"odinger Evolution Group.},
journal = {Mathematische Zeitschrift},
volume = {192},
year = {1986},
pages = {53-60},
zbl = {0594.35032},
url = {http://dml.mathdoc.fr/item/GDZPPN002431300}
}
Jensen, Arne. Commutator Methods and a Smoothing Property of the Schrödinger Evolution Group.. Mathematische Zeitschrift, Tome 192 (1986) pp. 53-60. http://gdmltest.u-ga.fr/item/GDZPPN002431300/