1. Lect Notes Comput Sci;D. S. Doermann,1998
2. Gonzalez, R. C., Woods, R. E.: Digital Image Processing. 3rd edn. Prentice-Hall PTR, NJ USA (2002)
3. Otsu, N.: A Threshold Selection Method from Gray-level Histograms. IEEE Transactions on Systems: Man and Cybernetics. 9(1) (1979) 62–66
4. Umbaugh, S. E.: Computer Vision and Image Processing: A Practical Approach using CVIPtools, Prentice-Hall PTR, NJ USA (1998)
5. Alexandrov, V. V., Gorsky, N. D.: Image Representation and Processing: A Recursive Approach. Mathematics and Its Applications, Vol. 261. Kluwer Academic Publishers, Dordrecht Boston London (1993)