Volume 22.2, Issue 44, January 1990, Pages 128-135
M.A. YOUSEF; M.A. ABD EL-KADER; A.R. EL-SHEIKH; S.M. EL-MAGAWRY
Volume 20.1, Issue 39, May 1988, Pages 40-44
S. EL-MAGAWRY; I.A. IBRAHIM S.; M.A. YOUSEF; A.A. EL-GHANNAM