@article{1138845880,
author = {Choda, Hisashi and Kijima, Y\=oichi and Nakagami, Yoshiomi},
title = {Some extremal properties in the unit ball of von Neumann algebras},
journal = {Kodai Math. Sem. Rep.},
volume = {21},
number = {1},
year = {1969},
pages = { 175-181},
language = {en},
url = {http://dml.mathdoc.fr/item/1138845880}
}
Choda, Hisashi; Kijima, Yōichi; Nakagami, Yoshiomi. Some extremal properties in the unit ball of von Neumann algebras. Kodai Math. Sem. Rep., Tome 21 (1969) no. 1, pp. 175-181. http://gdmltest.u-ga.fr/item/1138845880/