3Feng K. On difference schemes and symplectic geometry, Proceeding of the 1984 Beijing Symposium on D. D. , Bei- jing: Science Press, 1984, 42 - 58.
4Bridges T J. Muhi-symplectic Structures and Wave Propa- gation. Mathematical Proceedings of the Cambridge Philo- sophical Society, 1997, 121( 1 ) : 147 - 190.
5Hu W P, Han S M, Deng Z C, Fan W. Analyzing dynamic response of non-homogeneous string fixed at both ends. In- ternational Journal of Non-Linear Mechanics, 2012, 47 (10) :1111 - 1115.
6De Boer R, Svanadze M. Fundamental Solution of the System of Equations of Steady Oscillations in the Theory of Fluid-Saturated Porous Media[ J]. Transport in Porous Media, 2004, 56:39-50.
7Feng K. On Difference Schemes and Symplectic Geometry[C] ffProceeding of the 1984 Beijing Symposium on D D, 1984: 42-58.
8Bridge T J. Multi-Symplectic Structures and Wave Propagation [ J ]. Mathematical Proceedings of the Cambridge Philosophical Society, 1997, 121:147-190.
9Hu W P, Han S M, Deng Z C, Fan W. Analyzing Dynamic Response of Non-Homogeneous String Fixed at Both Ends[ J]. Inter- national Journal of Non-Linear Mechanics, 2012, 47 : 1111-1115.
10Hu W P, Deng Z C, Han S M,Zhang W R. Generalized Multi-Sympletic Integrators for a Class of Hamiltonian Nonlinear Wave PDEs [J]. Journal of Computational Physics, 2013, 235:394-406.
