el-hefny, a. (1964). forecasting for management of seasonal goods inventories. National Planning Institute.
Παραπομπή σε μορφή Chicago (17η εκδ.)el-hefny, amina. Forecasting for Management of Seasonal Goods Inventories. cairo: National Planning Institute, 1964.
Παραπομπή σε μορφή MLA (9th εκδ.)el-hefny, amina. Forecasting for Management of Seasonal Goods Inventories. National Planning Institute, 1964.