Journal of the Egyptian Mathematical Society
Journal of the Egyptian Mathematical Society > 2014 > 22 > 2 > 311-316
Journal of the Egyptian Mathematical Society > 2015 > 23 > 1 > 49-55
Journal of the Egyptian Mathematical Society > 2014 > 22 > 2 > 311-316
Journal of the Egyptian Mathematical Society > 2015 > 23 > 1 > 49-55