Mohammed Abdul Wahid Flayyih, and Ashwaq T.Kadhim. “The Role of the Four-Dimensional Product in Achieve Competitive Advantage”. Journal of Madenat Alelem University College, Vol. 12, no. 2, Dec. 2020, pp. 172-85, https://journal.mauc.edu.iq/index.php/JMAUC/article/view/374.