@article{MZ_1972__127_171782,
     author = {Gordon M. Petersen},
     title = {The {Relationship} of {Matrix} {Norms} to {Matrix} {Singularities.}},
     journal = {Mathematische Zeitschrift},
     pages = {365--369},
     publisher = {mathdoc},
     volume = {127},
     year = {1972},
     zbl = {0254.40004},
     url = {http://geodesic.mathdoc.fr/item/MZ_1972__127_171782/}
}