Volume 50, Issue 101, April 2004, Pages 319-329
T.A.A. Khalifa; Mary G. Abdel Malak; A.A. El-Menoufy; M.M. Ayoub
Volume 49, Issue 96, January 2003, Pages 283-292
S.M. Zaabel; T.A.A. Khalifa
Volume 42.1, Issue 83, October 1999, Pages 291-309
M.A.F. El-Sheltawi; Mary G. bdel-Malak; G. Abdel-Malak; T.A.A. Khalifa