@article{PORMA_1990__47_1_115701,
     author = {Cross, R.W.},
     title = {Unbounded linear transformations of upper {semi-Fredholm} type in normed spaces},
     journal = {Portugaliae mathematica},
     pages = {61--79},
     publisher = {mathdoc},
     volume = {47},
     number = {1},
     year = {1990},
     mrnumber = {1079507},
     zbl = {0734.47006},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_1990__47_1_115701/}
}