Volume 27, Issue 1, January 2013, Pages 21-31
M.R.K Ashry; K.M.R. Youssef; S.M.M. Abdou; A.A. El- Masry
Volume 24, Issue 1, January 2010, Pages 14-29
F.R.M Farrag; M.F.I El-Akram,; K.M.R. Youssef