V. S. Kapitonov, “Functional representation of the partition function and phase transitions in the Hubbard model”, J. Math. Sci., 83:1 (1997), 62–74
S. P. Cojocaru, V. A. Moskalenko, “A diagram method for the two-band Hubbard model”, Theoret. and Math. Phys., 97:2 (1993), 1290–1298
N. N. Bogolyubov, V. A. Moskalenko, “Superconductivity in the hubbard model with deviation from half filling”, Theoret. and Math. Phys., 92:2 (1992), 820–825
N. N. Bogolyubov, V. A. Moskalenko, “On the existence of superconductivity in the Hubbard model”, Theoret. and Math. Phys., 86:1 (1991), 10–19
S. I. Vakaru, M. I. Vladimir, V. A. Moskalenko, “Diagram technique for the Hubbard model. II. Metal-insulator transition”, Theoret. and Math. Phys., 85:2 (1990), 1185–1192