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on the regularity properties of the Coulomb interactions underlined in [3,4]
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Hoffmann-Ostenhof, T. Oe stergaard Soerensen: The electron density is smooth
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Analyticity of the density of electronic wave functions. Ark. Mat. 42, no. 1
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resonances curves. Ann. Inst. H. Poincar{\'e}, s. A, t. 45, no 4, 339-358
(1986). [4] M. Klein, A. Martinez, R. Seiler, X.P. Wang: On the
Born-Oppenheimer expansion for polyatomic molecules. Comm. Math. Phys. 143, no.
3, 607-639 (1992). The paper is published in Letters in Mathematical Physics
93, number 1, pp. 73-83, 2010. The original publication is available at
"www.springerlink.com".
