M. R. Ismail and M. J. Jweeg, “Natural Frequencies of Multi-Irregular Span Beams under Elastic Supports by Modal Analysis Method”, NUCEJ, vol. 18, no. 2, pp. 284–293, Jun. 2017, Accessed: Dec. 23, 2024. [Online]. Available: https://oldjournal.eng.nahrainuniv.edu.iq/index.php/main/article/view/190