[1] T. S. Newman and A. K. Jain, Computer Vision and Image Understanding 61, 231 (1995).

[2] K. Y. Song, M. Petrou, and J. Kittler, Proc. SPIE 1708, 99 (1992).

[3] D. M. Tsai and B. Hsiao, Pattern Recognition 34, 1285 (2001).

[4] L. N. De Castro and F. J. Von Zuben, Technical Report, RT DCA 01/99 (Brazil, 1999).