1. Hall, E.L.: Computer Image Processing and Recognition. Academic Press, New York (1979)
2. Jain, A.K.: Fundamentals of Digital Image Processing. Prentice Hall, Englewood Cliffs (1989)
3. Kawaguchi, E., Endo, T., Matsunaga, J.: Depth-first picture expression viewed from digital picture processing. IEEE Trans. on PAMI 5(4), 373–384 (1983)
4. Kawaguchi, E., Taniguchi, R.: Complexity of binary pictures and image thresholding - An application of DF-Expression to the thresholding problem. In: Proceedings of 8th ICPR, vol. 2, pp. 1221–1225 (1986)
5. Kawaguchi, E., Taniguchi, R.: The DF-Expression as an image thresholding strategy. IEEE Trans. on SMC 19(5), 1321–1328 (1989)