Khelil, F., M. Belhouari, N. Benseddiq, and A. Talha. “A Numerical Approach for the Determination of Mode I Stress Intensity Factors in PMMA Materials”. Engineering, Technology & Applied Science Research 4, no. 3 (June 14, 2014): 644-648. Accessed May 28, 2020. https://etasr.com/index.php/ETASR/article/view/442.