@article{GDZPPN002432900,
title = {Sharpened Forms of an Inequality of Von Neumann.},
journal = {Mathematische Zeitschrift},
volume = {194},
year = {1987},
pages = {7-14},
zbl = {0631.47004},
url = {http://dml.mathdoc.fr/item/GDZPPN002432900}
}
Fan, Ky. Sharpened Forms of an Inequality of Von Neumann.. Mathematische Zeitschrift, Tome 194 (1987) pp. 7-14. http://gdmltest.u-ga.fr/item/GDZPPN002432900/