Author/Authors :
Shoja، A. نويسنده Department of statistic and mathematics, Azad university of roodehen branch, Roodehen, Iran , , H. Mazaheri، H. Mazaheri نويسنده H. Mazaheri, H. Mazaheri , Sarikhani، R. نويسنده Department of Mathematics,Yazd University ,Yazd, Iran ,