@article{FORUM_1990__2_3_141636,
     author = {Niels Jacob},
     title = {Commutator {Estimates} for {Pseudodifferential} {Operators} with {Negative} {Definite} {Functions} as {Symbols.}},
     journal = {Forum mathematicum},
     pages = {155--162},
     publisher = {mathdoc},
     volume = {2},
     number = {3},
     year = {1990},
     zbl = {0693.35168},
     url = {http://geodesic.mathdoc.fr/item/FORUM_1990__2_3_141636/}
}