فهرس المقالات Mehdi Farrokhbakht Foumani المقاله 1 - The Development of a Hybrid Error Feedback Model for Sales Forecasting 20.1001.1.23221437.2021.9.34.7.4 10.52547/jist.9.34.131 Mehdi Farrokhbakht Foumani Sajad Moazami Goudarzi Journal of Information Systems and Telecommunication (JIST) , العدد 2 , السنة 9 , بهار 2021