H. A. Sallal, “Effect of the Addition Coconut Shell Powder on Properties of Polyurethane Matrix Composite”, NUCEJ, vol. 17, no. 2, pp. 203–210, Jun. 2014, Accessed: Mar. 18, 2026. [Online]. Available: http://oldjournal.eng.nahrainuniv.edu.iq/index.php/main/article/view/223