Kaxarboyevich , A. S. ., A. K. N. . o’g’li, and K. S. . Shuxratovich. “Free Vibrations of an Elastic Two-Layer Plate”. International Journal of Innovative Analyses and Emerging Technology, vol. 1, no. 4, Sept. 2021, pp. 121-6, https://openaccessjournals.eu/index.php/ijiaet/article/view/248.