• [1] N. I. Achieser and I. M. Glasmann, Theorie der linearen Operatoren im Hilbert-Raum, Akademie-Verlag, Berlin, 1954 (German). MR 0066560 (16,596f)
• [2] N. Bourbaki, Eléments de mathématique. XV. Première partie: Les structures fondamentales de l’analyse. Livre V: Espaces vectoriels topologiques. Chapitre I: Espaces vectoriels topologiques sur un corps valué. Chapitre II: Ensembles convexes et espaces localement convexes, Actualités Sci. Ind., no. 1189, Herman & Cie, Paris, 1953 (French). MR 0054161 (14,880b)
• [3] Earl A. Coddington, On maximal symmetric ordinary differential operators, Math. Scand. 4 (1956), 22–28. MR 0084748 (18,915c)
• [4] Earl A. Coddington, Generalized resolutions of the identity for closed symmetric ordinary differential operators, Proc. Nat. Acad. Sci. U.S.A. 42 (1956), 638–642. MR 0084749 (18,915d)
• [5] Earl A. Coddington, Generalized resolutions of the identity for symmetric ordinary differential operators, Ann. of Math. (2) 68 (1958), 378–392. MR 0103319 (21 #2094)
• [6] Einar Hille and Ralph S. Phillips, Functional analysis and semi-groups, American Mathematical Society Colloquium Publications, vol. 31, American Mathematical Society, Providence, R. I., 1957. rev. ed. MR 0089373 (19,664d)
• [7] N. Levinson, Transform and inverse transform expansions for singular self-adjoint differential operators, Illinois J. Math. 2 (1958), 224–235. MR 0096850 (20 #3332)
• [8] 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 (2,105a)
• [9] M. A. Neumark, Extremal spectral functions of a symmetric operator, Bull. Acad. Sci. URSS. Sér. Math. [Izvestia Akad. Nauk SSSR] 11 (1947), 327–344 (Russian, with English summary). MR 0024062 (9,447b)
• [10] A. V. Štraus, Generalized resolvents of symmetric operators, Izvestiya Akad. Nauk SSSR. Ser. Mat. 18 (1954), 51–86 (Russian). MR 0062954 (16,48e)

Bibliography

[1]

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

[2]

N. Bourbaki, Espaces vectoriels topologiques, Éléments de Mathématique, A. S. I. 1189, Hermann et Cie, Paris, 1953. MR 0054161 (14:880b)

[3]

E. A. Coddington, On maximal symmetric ordinary differential operators, Math. Scand. vol. 4 (1956) pp. 22-28. MR 0084748 (18:915c)

[4]

-, Generalized resolutions of the identity for closed symmetric ordinary differential operators, Proc. Nat. Acad. Sci. U.S.A. vol. 42 (1956) pp. 638-642. MR 0084749 (18:915d)

[5]

-, Generalized resolutions of the identity for symmetric ordinary differential operators, Ann. of Math. vol. 68 (1958) pp. 378-392. MR 0103319 (21:2094)

[6]

E. Hille and R. S. Phillips, Functional analysis and semi-groups, Amer. Math. Soc. Colloquium Publications, vol. 31, 1957. MR 0089373 (19:664d)

[7]

N. Levinson, Transform and inverse transform expansions for singular self-adjoint differential operators, Illinois J. Math. vol. 2 (1958) pp. 224-235. MR 0096850 (20:3332)

[8]

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

[9]

-, Extremal spectral functions of symmetric operators, Izv. Akad. Nauk SSSR. Ser. Mat. vol. 11 (1947) pp. 327-344. MR 0024062 (9:447b)

[10]

A. V. Štraus, Generalized resolvents of symmetric operators, Izv. Akad. Nauk SSSR. Ser. Mat. vol. 18 (1954) pp. 51-86. MR 0062954 (16:48e)