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• [3] M. Neumark, Spectral functions of a symmetric operator, Bull. Acad. Sci. URSS. Sér. Math. [Izvestia Akad. Nauk SSSR] 4 (1940), 277–318 (Russian, with English summary). MR 0002714

Bibliography

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N. I. Achieser and I. M. Glasmann, Theorie der linearen Operatoren im Hilbert-Raum, Akademie-Verlag, Berlin, 1954. MR 0066560 (16:596f)

[2]

R. C. Gilbert, Symmetric operators with singular spectral functions, Proc. Amer. Math. Soc. 21 (1969), 43-49. MR 0236736 (38:5030)

[3]

M. A. Naimark, Spectral functions of a symmetric operator, Izv. Akad. Nauk SSSR Ser. Mat. 4 (1940), 277-318. MR 0002714 (2:105a)