@article{GDZPPN002436035,
title = {Zur besten normalen Approximation komplexer Matrizen in der Euklidischen Norm.},
journal = {Mathematische Zeitschrift},
volume = {199},
year = {1988},
pages = {591-600},
zbl = {0648.15018},
url = {http://dml.mathdoc.fr/item/GDZPPN002436035}
}
Gabriel, Richard. Zur besten normalen Approximation komplexer Matrizen in der Euklidischen Norm.. Mathematische Zeitschrift, Tome 199 (1988) pp. 591-600. http://gdmltest.u-ga.fr/item/GDZPPN002436035/