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Translated from Matematicheskie Zametki, Vol. 55, No. 6, pp. 3–12, June, 1994.
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Azizov, T.Y., Khatskevich, V.L. On self-adjoint operators connected by inequalities and on their applications to problems of mathematical physics. Math Notes 55, 549–554 (1994). https://doi.org/10.1007/BF02110348
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DOI: https://doi.org/10.1007/BF02110348