COMPUTERS & MATHEMATICS WITH APPLICATIONS, vol. 51, no. 5, page. 713 - 720, 2006-03
APPLIED MATHEMATICS AND COMPUTATION, vol. 162, no. 3, page. 1135 - 1149, 2005-03-25
LECTURE NOTES IN COMPUTER SCIENCE, vol. 3045, page. 926 - 934, 2004-01