1. V. K. Ivanov, V. V. Vasin, and V. P. Tanana, Theory of Linear Ill-Posed Problems and Its Applications (Nauka, Moscow, 1978) [in Russian].
2. G. M. Vainikko and A. Yu. Veretennikov, Iterative Procedures in Ill-Posed Problems (Nauka, Moscow, 1986) [in Russian].
3. E. V. Arkharov and R. A. Shafiev, “Regularization Methods for the Constrained Pseudoinversion Problem with Inaccurate Data,” Zh. Vychisl. Mat. Mat. Fiz. 43, 347–353 (2003) [Comput. Math. Math. Phys. 43, 331–337 (2003)].
4. R. A. Shafiev, Pseudoinversion of Operators and Some Applications (Elm, Baku, 1989) [in Russian].
5. I. Yu. Yastrebova, Normal n-Connected Pseudosolution of an Equation and Regular Methods of Its Calculation, Available from VINITI, No. 3388-V99 (Nizhni Novgorod, 1999).