Kolkovska, Natalia, Milena Dimova, and Nikolay Kutev. “Nonexistence of Global Solutions to Double Dispersion Equations With Linear Restoring Force and Nonlinearities With Variable Coefficients”. Proceedings of the Bulgarian Academy of Sciences 76, no. 10 (October 31, 2023): 1486–1494. Accessed May 27, 2024. https://proceedings.bas.bg/index.php/cr/article/view/396.