1. ISBN 0-7167-1031-5 Janick, Jules.Horticultural Science. San Francisco: W.H. Freeman, 1979. Page 308.
2. B. L. Steward and L. F. Tian, “Real-time weed detection in outdoor field conditions,” in Proc. SPIE vol. 3543, Precision Agriculture and Biological Quality, Boston, MA, Jan. 1999, pp. 266-278.
3. J. E. Hanks, “Smart sprayer selects weeds for elimination,”Agricultural Research, vol. 44, no 4, pp. 15, 1996.
4. J. S. Weszka, C. R. Dyer, and A. Rosenfeld, “A comparative study of texture measures for terrain classification,”IEEE Transactions on Systems, Man, and Ccybernetics, SMC, vol. 6, pp. 269-285, 1976.
5. Rafael C. Gonzalez, Richard E. Woods,Digital Image Processing. 2nd ed. Delhi: Pearson Education, Inc, 2003, page 617,618