Butera, P.; Pernici, M. - In: Physica A: Statistical Mechanics and its Applications 387 (2008) 25, pp. 6293-6298
The high-temperature expansions of the spin-spin correlation function of the two-dimensional classical XY (planar rotator) model are extended by two terms, from order 24 through order 26, in the case of the square lattice, and by five terms, from order 15 through order 20, in the case of the...