@article{GDZPPN002302136,
title = {Spectral Analysis Using Ascent, Descent, Nullity and Defect.},
journal = {Mathematische Annalen},
volume = {189},
year = {1970},
pages = {197-214},
zbl = {0177.17102},
url = {http://dml.mathdoc.fr/item/GDZPPN002302136}
}
LAY, D.C. Spectral Analysis Using Ascent, Descent, Nullity and Defect.. Mathematische Annalen, Tome 189 (1970) pp. 197-214. http://gdmltest.u-ga.fr/item/GDZPPN002302136/