Ali Mahmud Ateiwi, Sadoon Abdullah Al-Obaidy and Iryna Volodymyrivna Komashynska
Journal of Applied Sciences 6 ( 8 ): 1845 - 1853 , 2006
Ali Mahmud Ateiwi and Iryna Volodymyrivna Komashynska
Journal of Mathematics and Statistics 2 ( 4 ): 460 - 463 , 2006