Volume 57, Issue 131, October 2011, Pages 1-13
I.A. EL-KEWAIEY; F.A. AL-TEDAWY; H.R. EL-HOFY
Volume 56, Issue 124, January 2010, Pages 1-10
H.H. ESSA; N.H. MAKAR; A.M. MANAA
Volume 51, Issue 107, October 2005, Pages 1-12
NAWAL A.M. MAZEN; HASNAA M.THABIT