Grafova, Galina Fedorovna, and Lev Jakovlevich Avrashkov. “ADDED VALUE AS A CRITERIA OF BUSSINESS EFFICIENCY ESTIMATION”. Среднерусский вестник общественных наук, vol. 1, no. 3, Mar. 2013, pp. 216-9, https://sredneruss-vestnik.owebs.ru/article/view/28971.