@article{MAN_1980__254_163490,
     author = {Johannes Sj\"ostrand},
     title = {Analytic {Singularities} and {Microhyperbolic} {Boundary} {Value} {Problems.}},
     journal = {Mathematische Annalen},
     pages = {211--256},
     publisher = {mathdoc},
     volume = {254},
     year = {1980},
     zbl = {0459.35007},
     url = {http://geodesic.mathdoc.fr/item/MAN_1980__254_163490/}
}