@article{3211,
author = {Cross, R.W.},
title = {Unbounded linear transformations of upper semi-Fredholm type in normed spaces},
journal = {Portugaliae mathematica},
volume = {47},
year = {1990},
pages = {61-79},
zbl = {0734.47006},
mrnumber = {1079507},
language = {en},
url = {http://dml.mathdoc.fr/item/3211}
}
Cross, R.W. Unbounded linear transformations of upper semi-Fredholm type in normed spaces. Portugaliae mathematica, Tome 47 (1990) pp. 61-79. http://gdmltest.u-ga.fr/item/3211/