1. Singh, S., Amin, A.: Neural Network Recognition of Hand-printed Characters. Neural Compute & Applica 8, 67–76 (1999)
2. Gonzalez, R.C., Woods, R.E.: Digital Image Processing
3. Yang, W., Ren, M., Yang, J.-y.: Object Area Algorithms Based on Chain Code in Digital Image. Computer Engineering 34(1), 30–33 (2008)
4. Qin, X., Cai, C., Zhou, C.: An algorithm for removing burr of skeleton. Journal of Huazhong University of Science and Technology (Natural Science) 32(12), 28–31 (2004)
5. Zhang, J., Sun, M.: Study on algorithm for skeleton features extraction of hand vein image. Journal of Computer Applications 27(1), 152–154 (2007)