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2. M. S. Green, J. Chem. Phys. 43, 1403 (1960). The parallel set P(r) of this paper is not the same as that of Eq. (1).
3. J. K. Percus and G. J. Yevick, Phys. Rev. 110, 1 (1958).
4. C. G. Gray and K. E. Gubbins, Theory of Molecular Fluids (Clarendon, Oxford, 1984), Vol. 1.
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