Kalbasi Ashtari, Hossein , Sa‘atchi, Mehdi . “A Study of ‘Allamah Tabataba’i’s Argument on Referring the Theory of “Gradation of Existence” to the Theory of the “Individual Unity of Existence”.” Kheradname-ye sadra, vol. 20, no. 1, 2014, pp. 1-10.