محمد حمید أ. ., & كاطع دواي ا. . . (2014). Study the Mechanical Behavior for Unsaturated Polyester Resin and Polystyrene. Journal of Engineering and Sustainable Development, 18(5), Ar 1-12. https://jeasd.uomustansiriyah.edu.iq/index.php/jeasd/article/view/943