INVESTIGATION OF SOME MECHANICAL PROPERTIES FOR NATURAL (EGGSHELL) AND INDUSTRIAL (CALCIUM CARBONATE) MATERIAL / REINFORCED WITH GLASS FIBER WITH POLYMER COMPOSITE. J. eng. sustain. dev. [Internet]. 2020 Nov. 1 [cited 2024 May 5];24(6):137-41. Available from: https://jeasd.uomustansiriyah.edu.iq/index.php/jeasd/article/view/99