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[2] Weichao Qian, Yong Li and Xue Yang, Multiscale KAM theorem for Hamiltonian systems. J. Differential Equations 266 (2019),1,70-86.
[3] Weichao Qian, Yong Li and Xue Yang Persistence of Lagrange invariant tori at tangent degeneracy. J. Differential Equations 268(2020),9,5078-5112.
[4] Weichao Qian, Xue Yang and Yong LI, KAM persistence for multiscale generalized Hamiltonian systems. Commun. Math. Sci.21(2023),2,559-579.
[5] Weichao Qian, Yong Li and Xue Yang, Melnikov's conditions in matrices.J. Dynam Differential Equations 32(2020),4,1779-1795.