Author/Authors :
OSTAD RAHIMI، M نويسنده Department of mathematics, Tehran North Branch, Islamic Azad University, Tehran, Iran , , MOSTAFAEI، H. R. نويسنده Department of Statistics, Tehran North Branch, Islamic Azad University, Tehran, Iran & Department of Economics Energy, Institute for International E , , ZAEEMBASHI، A. نويسنده Department of Mathematics, Faculty of Science, Shahid Rajaee Teacher Training University, Tehran, 16785-136, I. R. Iran ,