@article{MAN_1980__253_163478,
     author = {R. Loewy},
     title = {Extreme {Points} of a {Convex} {Subset} of the {Cone} of {Positive} {Semidefinite} {Matrices.}},
     journal = {Mathematische Annalen},
     pages = {227--232},
     publisher = {mathdoc},
     volume = {253},
     year = {1980},
     zbl = {0426.46008},
     url = {http://geodesic.mathdoc.fr/item/MAN_1980__253_163478/}
}