1. A.V. Oppenheim, Signals and Systems (Prentice-Hall, USA, 1982)
2. R.C. Gonzalez, R.E. Woods, Digital Image Processing (Prentice-Hall, USA, 2007)
3. M. Bertero, P. Boccacci, Introduction to Inverse Problems in Imaging (IOP, UK, 1998)
4. A.N. Tikhonov, Y.V. Arsenin, Solutions of Ill-Posed Problems (Halsted Press, New York, 1977)
5. C.W. Helstrom, Image restoration by the method of least squares. J. Opt. Soc. Am. 57, 297–303 (1967)