@article{10_4064_sm179_1_6,
     author = {Joachim Toft},
     title = {Wave front set for positive operators and for positive
elements in non-commutative convolution algebras},
     journal = {Studia Mathematica},
     pages = {63--80},
     publisher = {mathdoc},
     volume = {179},
     number = {1},
     year = {2007},
     doi = {10.4064/sm179-1-6},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.4064/sm179-1-6/}
}