Volume 23, Issue 3, December 2020, Pages 385-395
S. Abo Bakr; H. G. Helal; E. Y. Eid; H. M. El Shaer
Volume 22, Issue 1, April 2019, Pages 63-78
S. Abo Bakr
Volume 18, Issue 3, December 2015, Pages 359-371
H. G. Helal