Volume 31.1, Issue 61, April 1994, Pages 135-162
S.S. EL-BALLAL; K. EL-ZANATY
Volume 30.2, Issue 60, January 1994, Pages 306-319
T.Y. ABD-EL-MOTELIB; S.S. EL-BALLAL; BAHY EL-GAMAL GALAL
Volume 28.2, Issue 56, January 1993, Pages 171-175
S.S. EL-BALLAL; S.H. AFIFI
Volume 28.1, Issue 55, October 1992, Pages 158-173
H.A. SALEM; S.S. EL-BALLAL; A.Sh. SEDDEK
Volume 27.1, Issue 53, April 1992, Pages 47-54
A.M. KELANY; S.H. AFIFI; S.S. EL-BALLAL
Volume 27.1, Issue 53, April 1992, Pages 295-304
B. SALEM; S.S. EL-BALLAL