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2. V. P. Maslov, “On the appearance of the λ-point in a weakly nonideal Bose gas and the two-liquid Thiess-Landau model,” Russian J. Math. Phys. 16(2), 146–172 (2009).
3. Mathematical Encyclopedia (Soviet Encyclopedia, Moscow, 1977), Vol. 1 [in Russian].
4. V. V. Kozlov, Thermal Equilibrium According to Gibbs and Poincar’e (Institute for Computer Studies, Moscow, 2002) [in Russian].
5. Ludwig Boltzmann: Papers and Speeches (Nauka, Moscow, 1970) [in Russian].