1. Operators with finite ascent and descent;Caradus;Pacific J. Math.,1966
2. Analyse mathématique et calcul numérique;Dautray,1988
3. Classes of Operators, vol. I;Gohberg,1990
4. Behaviour of the space of zero elements with finite-dimensional salient on the Riesz kernel under perturbations of the operator;Goldman;Dokl. Akad. Nauk SSSR,1975
5. Ascent, descent, and compact perturbations;Grabiner;Proc. Amer. Math. Soc.,1978