“Formation of an optimal investment portfolio of the common stocks by using the model of simple rating – an empirical study in the Iraqi stock exchange” (2021) Journal of Al-Rafidain University College For Sciences ( Print ISSN: 1681-6870 ,Online ISSN: 2790-2293 ), 26(1), pp. 133–150. doi:10.55562/jrucs.v26i1.430.