KAM tori for a nonlinear beam equation with an almost periodic potential based on the space variable.

Sixue Zhu Jie Rui KAM tori for a nonlinear beam equation with an almost periodic potential based on the space variable. 109045 2025 150 Commun. Nonlinear Sci. Numer. Simul. https://doi.org/10.1016/j.cnsns.2025.109045 db/journals/cnsns/cnsns150.html#ZhuR25 streams/journals/cnsns