@article{MS2_1958__6_165687,
     author = {Lars H\"ormander},
     title = {On the {Uniqueness} of the {Cauchy} {Problem.}},
     journal = {Mathematica Scandinavica},
     pages = {213--225},
     publisher = {mathdoc},
     volume = {6},
     year = {1958},
     zbl = {0088.30201},
     url = {http://geodesic.mathdoc.fr/item/MS2_1958__6_165687/}
}