Volume 29.1, Issue 57, April 1993, Pages 143-150
H.S. ALI; S.I. IBRAHIM; A. EL-R. THABET
Volume 24.2, Issue 48, January 1991, Pages 158-163
R.S. REFAIE; SEHAM M.A.; A. EL-R. THABET; A.A.M. EL-TIMAWY