1. H.W. Engl, Stability of solutions to linear operator equations of the first and second kinds under perturbation of the operator with rank change, in: G. Herman, F. Natterer (eds.), Mathematical Aspects of Computerized Tomography, Lecture Notes in Medical Informatics 8, Springer 1981, 13–28.
2. H.W. Engl, Necessary and sufficient conditions for convergence of regularization methods for solving linear operator equations of the first kind, Numer. Funct. Anal. Opt. 3 (1981), 201–222.
3. H.W. Engl, On least-squares collocation for solving linear integral equations of the first kind with noisy right-hand side, Boll. di Geodesia e Sc. Affini 41, 3 (1982), to appear.
4. H.W. Engl, Regularization by least-squares collocation, in: P. Deuflhard-E. Hairer (eds.), Inverse Problems in Differential and Integral Equations, Birkhäuser 1983, to appear.
5. C.W. Groetsch, Generalized Inverses of Linear Operators, Dekker 1977.