Najafgholipour, Mohammadamir, and Navid Soodbakhsh. “Modified Differential Transform Method for Solving Vibration Equations of MDOF Systems”. Civil Engineering Journal 2, no. 4 (May 7, 2016): 123–139. Accessed October 15, 2025. https://www.civilejournal.org/index.php/cej/article/view/94.