@article{MZ_1983__184_173348,
     author = {Toshiyuki Takasaki and Jun Tomiyama},
     title = {On the {Geometry} of {Positive} {Maps} in {Matrix} {Algebras.}},
     journal = {Mathematische Zeitschrift},
     pages = {101--108},
     year = {1983},
     volume = {184},
     zbl = {0511.46050},
     url = {http://geodesic.mathdoc.fr/item/MZ_1983__184_173348/}
}