Volume 22, Issue 1, January 1999, Pages 21-28
A.S. ZEIN EL-DIN; A.E. EL-SABBE
Volume 21, Issue 2, April 1998, Pages 71-89
A.S. ZEIN EL DIN; Z. MOHAMED; A.A. EL-HEFNAWY; A.S. ABDEL-GHAFAR