@article{1200780359,
author = {Harada, Manabu},
title = {Generalizations of Nakayama ring. VI. Right ${\rm US}$-$n$ rings; $n=3,4$},
journal = {Osaka J. Math.},
volume = {24},
number = {1},
year = {1987},
pages = { 785-815},
language = {en},
url = {http://dml.mathdoc.fr/item/1200780359}
}
Harada, Manabu. Generalizations of Nakayama ring. VI. Right ${\rm US}$-$n$ rings; $n=3,4$. Osaka J. Math., Tome 24 (1987) no. 1, pp. 785-815. http://gdmltest.u-ga.fr/item/1200780359/