Liouville's theorem for infinitely neighbor-coupled hamiltonian system on infinite-dimensional torus (Japanese)

[Comments] This can be considered a problem of a "singular Hamiltonian system" in the sense of being the limit of a "normal Hamiltonian system," but more narrowly, it may also be possible to consider a problem of a "singular integrable system" (an example of a neighbor-coupled system would be the Toda lattice).