Yang, Some exact results for the many-body problem in one dimension with delta-function interaction, Phys. Rev. Lett., Band 19, 1967, S. 1312–1314, doi:10.1103/PhysRevLett.19.1312
Baxter, Solvable eight-vertex model on an arbitrary planar lattice, Phil. Trans. Royal Soc., Band 289, 1978, S. 315–346, doi:10.1098/rsta.1978.0062, JSTOR:75051
Baxter, Solvable eight-vertex model on an arbitrary planar lattice, Phil. Trans. Royal Soc., Band 289, 1978, S. 315–346, doi:10.1098/rsta.1978.0062, JSTOR:75051