“The Effect of Adding Alumina Phases (alpha and Amorphous) to Improve the Mechanical Properties (Compressive Strength and Hardness) of Polyester Matrix Composites”. Journal of Engineering and Sustainable Development 18, no. 6 (November 1, 2014): 202–211. Accessed July 3, 2024. https://jeasd.uomustansiriyah.edu.iq/index.php/jeasd/article/view/931.