I. G. Brankov, V. A. Zagrebnov, I. S. Tonchev, “Asymptotically exact solution of the generalized Dicke model”, Theor Math Phys, 22, № 1, 1975, 13
N. N. Bogolyubov, V. N. Plechko, N. F. Repnikov, “Majorizing estimates in the method of approximating (trial) Hamiltonians”, Theor Math Phys, 24, № 3, 1975, 886
F.W. Nijhoff, H.W. Capel, “Separable interactions and liquid 3He”, Physica A: Statistical Mechanics and its Applications, 111, № 3, 1982, 371
Masha Shcherbina, Brunello Tirozzi, Camillo Tassi, “Quantum Hopfield Model”, Physics, 2, № 2, 2020, 184
L.W.J. den Ouden, H.W. Capel, J.H.H. Perk, “Systems with separable many-particle interactions. II”, Physica A: Statistical Mechanics and its Applications, 85, № 3, 1976, 425
N. Bogolyubov, “New method of defining quasiaverages”, Theor Math Phys, 5, № 1, 1970, 1038
J.H.H. Perk, H.W. Capel, L.W.J. den Ouden, “Convex-envelope formulation for separable many-particle interactions”, Physica A: Statistical Mechanics and its Applications, 89, № 3, 1977, 555
K.K Singh, “Statistical mechanics of superfluid models”, Annals of Physics, 75, № 1, 1973, 38
G. A. Raggio, “The free energy of the spin-boson model”, J Stat Phys, 53, № 3-4, 1988, 565
V.N. Plechko, “Critical amplitudes and “cosine of the angle” between order parameters”, Physics Letters A, 83, № 7, 1981, 357