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 4.1, Issue 7, January 1977, Pages 117-124
o.A., Atalah; M.M. Ayoub; A.A. Hegazy