Abstract
The paper contains a survey of papers reviewed in Ref. Zh. Matematika from 1953–1978 on the theory of linear operators in (mainly Hibert) spaces with indefinite metric and their applications to various domains of mathematics and mechanics. As a preliminary, the needed results on the geometry of spaces with indefinite metric are described.
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T. Ya. Azizov, “On invariant subspaces of a family of commuting operators in a Πϰ space,” Funkts. Anal. Prilozhen.,6, No. 3, 59–60 (1972).
T. Ya. Azizov, “On completely continuous operators, self-adjoint with respect to a degenerate indefinite metric,” Mat. Issled., Vol. 7, Kishinev, Akad. Nauk Mold. SSR, 237–240 (1972).
T. Ya. Azizov, “Dissipative operators in a Hilbert space with indefinite metric,” Izv. Akad. Nauk SSSR, Ser. Mat.,37, No. 3, 639–662 (1973).
T. Ya. Azizov, “On invariant subspaces of commutative families of operators in a space with indefinite metric,” Ukr. Mat. Zh.,28, No. 3, 293–299 (1976).
T. Ya. Azizov, “On uniformly ℐ-expanding operators and focusing plus-operators,” School on the Theory of Operators in Functional Spaces (Abstracts of Reports), Minsk (1978), p. 5.
T. Ya. Azizov and M. D. Dragileva, “On invariant subspaces of operator-commutative families of operators in a space with indefinite metric,” Tr. NII Mat. Voronezh., Univ., No. 17, 3–7 (1975).
T. Ya. Azizov and E. I. Iokhvidov, “On invariant subspaces of maximal ℐ-dissipative operators,” Mat. Zametki,12, No. 6, 747–754 (1972).
T. Ya. Azizov and I. S. Iokhvidov, “Linear operators in Hilbert spaces with G-metric,” Usp. Mat. Nauk,26, No. 4, 43–92 (1971).
T. Ya. Azizov and I. S. Iokhvidov, “Criteria for completeness and basedness of root vectors of a completely continuous ℐ-self-adjoint operator in a Pontryagin Πϰ space,” Mat. Issled.,6, No. 1, Kishinev, Akad. Nauk Mold. SSR, 158–161 (1971).
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T. Ya. Azizov and V. A. Senderov, “On spectra and invariant subspaces of unitary operators in Banach spaces with indefinite metric,” Dokl. Akad. Nauk Arm. SSR,54, No. 1, 13–16 (1972).
T. Ya. Azizov and V. A. Senderov, “On the structure and spectrum ofℐ -unitary operators of certain classes,” Tr. NII Mat. Voronezh. Univ., No. 11, 3–9 (1973).
T. Ya. Azizov and E. B. Usvyatsova, “Existence of special nonnegative subspaces of ℐ-dissipative operators,” Sib. Mat. Zh.,18, No. 1, 216–218 (1977).
T. Ya. Azizov and E. B. Usvyatsova, “On the completeness and basedness of characteristic and adjoint vectors of operators of class ℋ(H),” Ukr. Mat. Zh.,30, No. 1, 86–88 (1978).
T. Ya. Azizov and V. A. Shtraus, “On the completeness of systems of root vectors of a definable operator in a Banach space with a Hermitian form,” Tr. NII Mat. Voronezh. Univ., No. 5, 1–6 (1972).
R. V. Akopyan, “On the trace formula in the theory of perturbations for ℐ-nonnegative operators,” Dokl. Akad. Nauk Arm. SSR,57, No. 4, 193–199 (1973).
R. V. Akopyan, “On the theory of perturbations of a ℐ-positive operator,” Funkts. Anal. Prilozhen.,9, No. 2, 61–62 (1975).
R. V. Akopyan, “On the theory of spectral functions of a ℐ-nonnegative operator,” IAN Arm. SSR, Ser. Fiz.-Mat. Nauk,13, No. 2, 114–121 (1978).
N. K. Askerov, S. G. Krein, and G. I. Laptev, “The problem of oscillations of a viscous fluid and the operator equations connected with it,” Funks. Anal. Prilozhen.,2, 21–31 (1968).
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Yu. M. Berezanskii, Expansions in Eigenfunctions of Self-Adjoint Operators, Amer. Math. Soc. (1968).
F. A. Berezin, “On Lie models,” Mat. Sb.,60, No. 4, 425–446 (1963).
Ya. Bognar, “On the existence of a square root of an operator, self-adjoint with respect to an indefinite metric,” Magyar Tud. Akad. Mat. Kutató Int. Közl.,6, No. 3, 351–363 (1961).
Ya. Bognar, “On a discontinuity phenomenon of a scalar product in spaces with indefinite metric,” Usp. Mat. Nauk,17, No. 1, 157–159 (1962).
Ya. Bognar, “On certain relations between nonnegativity properties of operators in spaces with indefinite metric,” Magyar Tud. Akad. Mat. Kutató Int. Közl.,8, No. 1–2, 201–212 (1963).
Ya. Bognar, “On certain relations between nonnegativity properties of operators in spaces with indefinite metric. II,” Stud. Sci. Math. Hung.,1, No. 1–2, 97–102 (1966).
Ya. Bognar, “On certain relations between nonnegativity properties of operators in spaces with indefinite metric. III,” Stud. Sci. Math. Hung.,1, No. 3–4, 419–426 (1966).
Ya. Bognar, “Remark on doubly strict plus-operators,” Mat. Issled.,8, No. 1 (27), Kishinev, Akad. Nauk Mold. SSR, 217–219 (1973).
M. L. Brodskii, “On properties of an operator mapping the nonnegative part of a space with indefinite metric into itself,” Usp. Mat. Nauk,14, No. 1, 147–152 (1959).
M. S. Brodskii, “On operators with kernels with imaginary components,” Acta Sci. Math.,27, No. 3–4, 147–155 (1966).
M. S. Brodskii, “Unitary angular operators and their characteristic functions,” Usp. Mat. Nauk,33, No. 4, 141–168 (1978).
M. I. Vishik, “The method of orthogonal projections for general self-adjoint equations,” Dokl. Akad. Nauk SSSR,58, 957–960 (1947).
I. M. Gel'fand and V. B. Lidskii, “On the structure of the domain of stability of linear canonical systems of differential equations with periodic coefficients,” Usp. Mat. Nauk,10, No. 1, 3–40 (1955).
V. Gerish, “Remark on the papers on N. K. Bari on biorthogonal systems and bases in a Hilbert space,” Dokl. Akad. Nauk SSSR,200, No. 5, 1018–1019 (1971).
V. Gerish and A. Gerish, “Pontryagin space and convergence of the method of Bubnov-Galerkin,” Dokl. Akad. Nauk SSSR,193, No. 6, 1218–1221 (1970).
Yu. P. Ginzburg, “On ℐ-nonexpanding operator-functions,” Dokl. Akad. Nauk SSSR,117, No. 2 (1957).
Yu. P. Ginzburg, “On ℐ-nonexpanding operators in a Hilbert space,” Nauch. Zap. Fiz.-Mat. Fak. Odessk. Gos. Pedagog. Inst.,22, No. 1, 13–20 (1958).
Yu. P. Ginzburg, “On projections in a Hilbert space with bilinear metric,” Dokl. Akad. Nauk SSSR,139, No. 4, 775–778 (1961).
Yu. P. Ginzburg, “On subspaces of a Hilbert space with indefinite metric,” Nauchn. Zap. Kafedr Mat., Fiz. Estestbozn. Odessk. Gos. Pedagog. Inst.,25, No. 2, 3–9 (1961).
Yu. P. Ginzburg, “Maximum principle for ℐ-nonexpanding operator-functions and some of its consequences,” Izv. Vyssh. Mat. Uchebn. Zaved., No. 1 (32), 42–53 (1963).
Yu. P. Ginzburg, “On multiplicative representations of ℐ-nonexpanding operator-functions,” Mat. Issled.,2, No. 3, Kishenev, Akad. Nauk Mold. SSR, 20–51 (1967).
Yu. P. Ginzburg and I. S. Iokhvidov, “On new results on the geometry and the theory of operators in spaces with indefinite metric,” in: Proceedings of the Fourth All-Union Mathematical Congress, 1961 [in Russian], Vol. 2, Nauka, Leningrad (1964).
Yu. P. Ginzburg and I. S. Iokhvidov, “Studies on the geometry of infinite-dimensional spaces with bilinear metric,” Usp. Mat. Nauk,17, No. 4, 3–56 (1962).
I. M. Glazman and Yu. I. Lyubich, Finite-Dimensional Linear Analysis in Problems [in Russian], Nauka, Moscow (1969).
V. P. Glukhov, “On linear correspondences in spaces with indefinite metric,” in: Functional Analysis [in Russian], Vol. 1, Ul'yanovsk (1973), pp. 37–46.
V. P. Glukhov, “On Cayley transforms of linear correspondences,” in: Functional Analysis [in Russian], Vol. 1, Ul'yanovsk (1973), pp. 47–50.
V. P. Glukhov, “On extensions of ℐ-symmetric correspondences,” in: Functional Analysis [in Russian], Vol. 2, Ul'yanovsk, 1974 (1975), pp. 12–15.
V. P. Glukhov and A. A. Nikonov, “On extensions and generalized resolvents of ℐ-symmetric and ℐ-dissipative relations,” in: Functional Analysis [in Russian], Vol. 7, Ul'yanovsk (1976), pp. 53–59.
V. I. Gorbachuk (V. I. Plyushcheva), “On indefinite representations of continuous Hermitian-indefinite kernels,” Dokl. Akad. Nauk SSSR,145, No. 3, 534–537 (1962).
V. I. Gorbachuk (V. I. Plyushcheva), “On integral representations of Hermitian-indefinite matrices with τ negative squares,” Ukr. Mat. Zh.,14, No. 1, 30–39 (1962).
V. I. Gorbachuk (V. I. Plyushcheva), “On integral representations of Hermitian-indefinite kernels (case of many variables),” Ukr. Mat. Zh.,16, No. 2, 232–236 (1964).
V. I. Gorbachuk (V. I. Plyushcheva), “On integral representations of Hermitian-indefinite kernels,” Ukr. Mat. Zh.,17, No. 3, 43–58 (1965).
V. I. Gorbachuk (V. I. Plyushcheva), “On the uniqueness of representations of Hermitian-indefinite functions and sequences,” Ukr. Mat. Zh.,18, No. 2, 107–113 (1966).
V. I. Gorbachuk (V. I. Plyushcheva), “On extensions of real Hermitian-indefinite functions with one negative square,” Ukr. Mat. Zh.,19, No. 4, 119–125 (1967).
V. I. Gorbachuk (V. I. Plyushcheva) and M. L. Gorbachuk, “On representations of vacuum averaging field operators in a space with indefinite metric,” Ukr. Mat. Zh.,18, No. 6, 108–111 (1966).
I. Ts. Gokhberg and M. G. Krein, “Basic situations of defect numbers, root numbers, and indices of linear operators,” Usp. Mat. Nauk,12, No. 2, 43–118 (1957).
I. C. Gohberg and M. G. Krein, Introduction to the Theory of Linear Nonself-Adjoint Operators, Amer. Math. Soc. (1969).
Yu. L. Dalecki and M. G. Krein, Stability of Solutions of Differential Equations in Banach Spaces, Amer. Math. Soc. (1974).
Yu. L. Daletskii and E. A. Fadeeva, “Hyperbolic equations with operator coefficients and ultraparabolic systems,” Ukr. Mat. Zh.,24, No. 1, 92–94 (1972).
L. S. Dashnits, “On the completeness of the system of finite-dimensional invariant subspaces of a pair of differential operators,” Tr. Odessk. Tekhnol. Inst.,6, 163–169 (1954).
V. I. Derguzov, “On stability of solutions of Hamiltonian equations in a Hilbert space with unbounded periodic operator coefficients,” Dokl. Akad. Nauk SSSR,152, No. 6, 1294–1296 (1963).
V. I. Derguzov, “Sufficient conditions for stability of Hamiltonian equations with unbounded periodic operator coefficients,” Mat. Sb.,64, No. 3, 419–435 (1964).
V. I. Derguzov, “Necessary conditions for strong stability of Hamiltonian equations with unbounded periodic operator coefficients,” Vestn. Leningr. Univ., No. 19, 18–30 (1964).
V. I. Derguzov, “On stability of solutions of Hamilton's equations with unbounded periodic operator coefficients,” Mat. Sb.,63, No. 4, 591–619 (1964).
V. I. Derguzov, “Domain of strong stability of linear Hamiltonian equations with periodic operator coefficients,” Vestn. Leningr. Univ., No. 13, 20–30 (1969).
V. A. Derkach, “On the signature of defective subspaces ofπ-Hermitian operators with nondense domain of definition in Πϰ spaces,” Dokl. Akad. Nauk Ukr. SSR, A, No. 7, 579–581 (1977).
V. A. Derkach, “Unbounded operator nodes in Πϰ space and their characteristic operator-functions,” Donetsk. Univ., Donetsk (1977).
A. V. Efimov and V. P. Potapov, “ℐ-expanding matrix-functions and their role in analytic number theory,” Usp. Mat. Nauk,28, No. 1, 65–130 (1973).
E. I. Iokhvidov, “On maximal ℐ-dissipative operators,” in: VGU Compendium of Student Scientific Papers [in Russian], No. 5 (Natural Sciences), Voronezh (1972), pp. 74–79.
E. I. Iokhvidov, “On extensions of isometric operators in a Hilbert space with indefinite metric,” Tr. NII Mat. Voronezh. Univ., No. 14, 21–31 (1974).
E. I. Iokhvidov, “On properties of a linear-fractional operator transformation,” Usp. Mat. Nauk,30, No. 4, 243–244 (1975).
E. I. Iokhvidov, “On ℐ-unitary extensions of ℐ-isometric operators with equal and finite defect numbers,” Tr. NII Mat. Voronezh. Univ., No. 17, 34–41 (1975).
E. I. Iokhvidov, “Description of ℐ-unitary extensions of ℐ-isometric operators with equal and finite defect numbers,” Dokl. Akad. Nauk SSSR,228, No. 4, 783–786 (1976).
E. I. Iokhvidov and I. S. Iokhvidov, “On the global inversion of a linear-fractional operator transformation,” Tr. NII Mat. Voronezh. Univ., No. 11, 64–70 (1973).
E. I. Iokhividov and V. A. Senderov, “Linear-fractional operator transformations and certain of their applications,” Tr. NII Mat. Voronezh. Univ., No. 5, 52–58 (1972).
I. S. Iokhvidov, “Unitary operators in a space with indefinite metric,” Zap. NII Mat. Mekh. KhGU Khark. Mat. Ob-va,21, 79–86 (1949).
I. S. Iokhvidov, “On spectra of Hermitian and unitary operators in a space with indefinite metric,” Dokl. Akad. Nauk SSSR,71, 225–228 (1950).
I. S. Iokhvidov, “On the theory of indeterminat Toeplitz forms,” Dokl. Akad. Nauk SSSR,101, No. 2, 213–216 (1955).
I. S. Iokhvidov, “Linear operators in spaces with indefinite metric,” in: Proceedings of the Third All-Union Mathematical Congress,3, 254–261 (1958).
I. S. Iokhvidov, “Regular and projectionally complete lineals in spaces with general Hermitian-bilinear metric,” Dokl. Akad. Nauk SSSR,139, No. 4, 791–794 (1961).
I. S. Iokhvidov, “On boundedness of ℐ-isometric operators,” Usp. Mat. Nauk,16, No. 4, 167–170 (1961).
I. S. Iokhvidov, “On certain classes of operators in a space with general indefinite metric,” in: Functional Analysis and Its Applications [in Russian], Izd. Akad. Nauk Azerb. SSR, Baku (1961), pp. 90–95.
I. S. Iokhvidov, “Singular lineals in spaces with arbitrary Hermitian-bilinear metric,” Usp. Mat. Nauk,17, No. 4, 127–133 (1962).
I. S. Iokhvidov, “On operators with completely continuous iterates,” Dokl. Akad. Nauk SSSR,153, No. 2, 258–261 (1963).
I. S. Iokhvidov, “New characterization of Πϰ spaces,” in: Scientific Conference of the Civil Engineering Institute, Odessa (1964), p. 173.
I. S. Iokhvidov, “On a lemma of K. Fan, generalizing A. N. Tikhonov's fixed point principle,” Dokl. Akad. Nauk SSSR,159, No. 3, 501–504 (1964).
I. S. Iokhvidov, “On singular lineals in Πϰ spaces,” Ukr. Mat. Zh.,16, No. 3, 300–308 (1964).
I. S. Iokhvidov, “G-isometric and ℐ-semiunitary operators in a Hilbert space,” Usp. Mat. Nauk,20, No. 3, 175–181 (1965).
I. S. Iokhvidov, “On maximal definite lineals in a Hilbert space with G-metric,” Ukr. Mat. Zh.,17, No. 4, 22–28 (1965).
I. S. Iokhvidov, “Banach spaces with ℐ-metric ℐ-nonnegative operators,” Dokl. Akad. Nauk SSSR,169, No. 2, 259–261 (1966).
I. S. Iokhvidov, “ℐ-nonexpanding operators in a Banach space,” Dokl. Akad. Nauk SSSR,169, No. 3, 519–522 (1966).
I. S. Iokhvidov, “Linear-fractional transformations of ℐ-nonexpanding operators,” Dokl. Akad. Nauk Arm. SSR,42, No. 1, 3–8 (1966).
I. S. Iokhvidov, “Real sequences of class ℐ1,” Dokl. Akad. Nauk Arm. SSR,42, No. 5, 268–273 (1966).
I. S. Iokhvidov, “Unitary extensions of isometric operators in a Pontryagin space Π1 and extensions in classB 1 of finite sequences of classB 1;n ,” Dokl. Akad. Nauk SSSR,173, No. 4, 758–761 (1967).
I. S. Iokhvidov, “On spectral trajectories, generated by unitary extensions of isometric shift operators in a finite-dimensional π1 space,” Dokl. Akad. Nauk SSSR,173, No. 5, 1002–1005 (1967).
I. S. Iokhvidov, “On Banach spaces with ℐ-metric and certain classes of linear operators in these spaces,” Izv. Akad. Nauk Mold. SSR, Ser. Fiz.-Tekh. Mat. Nauk, No. 1, 60–80 (1968).
I. S. Iokhvidov, “On a class of linear-fractional operator transformations,” in: Compendium on Papers on Function Spaces and Operator Equations [in Russian], Voronezh (1970), pp. 18–44.
I. S. Iokhvidov, Hankel and Toeplitz Matrices and Forms. Algebraic Theory [in Russian], Nauka, Moscow (1974).
I. S. Iokhvidov, “On spaces of finitary sequences with nondegenerate Hermitian form,” Tr. NII Mat. Voronezh. Univ., No. 20, 30–38 (1975).
I. S. Iokhvidov, “On (r, k)-characteristic rectangular Hankel matrices,” Dokl. Akad. Nauk SSSR,233, No. 2, 276–279 (1977).
I. S. Iokhvidov, “On extensions of rectangular Hankel matrices,” Dokl. Akad. Nauk SSSR,233, No. 3, 29–32 (1977).
I. S. Iokhvidov and M. G. Krein, “Spectral theory of operators in a space with indefinite metric,” Usp. Mat. Nauk,11, No. 4, 169–171 (1956).
I. S. Iokhvidov and M. G. Krein, “Spectral theory of operators in spaces with indefinite metric. I,” Tr. Mosk. Mat. Ob-va,5, 367–432 (1956).
I. S. Iokhvidov and M. G. Krein, “Remark on the paper ‘Spectral theory of operators in spaces with indefinite metric. I’, ” Tr. Mosk. Mat. Ob-va,6, 486 (1957).
I. S. Iokhvidov and M. G. Krein, “Spectral theory of operators in spaces with indefinite metric. II,” Tr. Mosk. Mat. Ob-va,8, 413–496 (1959).
I. S. Iokhvidov and M. G. Krein, “Letter to the editor (in connection with the paper ‘Spectral theory of operators in spaces with indefinite metric’),” Tr. Mosk. Mat. Ob-va,15, 452–454 (1966).
I. S. Iokhividov and V. A. Senderov, “On boundedness of ℐ-semiunitary operators in Banach spaces with ℐ-metric,” Mat. Issled.,5, No. 4, Kishenev, Akad. Nauk Mold. SSR, 166–170 (1970).
A. G. Kostyuchenko and M. B. Orazov, “On certain properties of roots of a self-adjoint quadratic bundle,” Funkts. Anal. Prilozhen.,9, No. 4, 28–40 (1975).
M. A. Krasnosel'skii and A. V. Sobolev, “On cones of finite rank,” Dokl. Akad. Nauk SSSR,225, No. 6, 1256–1259 (1975).
M. G. Krein, “On loaded integral equations whose distribution functions are not monotone,” in: Memoirs of the Academy [in Russian], Grave (1940), pp. 88–103.
M. G. Krein, “On the linear cycle of a continuous operator in special functionals with two norms,” Zh. Inst. Mat. Akad. Nauk Ukr. SSR,9, 104–129 (1947).
M. G. Krein, “Spiral lines in a Lobachevskii space of an infinite number of dimensions and Lorentz transformations,” Usp. Mat. Nauk,3, No. 3, 158–160 (1948).
M. G. Krein, “On the Hermitian operator with indirect functions,” in: Memoirs of the Mathematics Institute, Academy of Sciences of the Ukrainian SSR,10, 83–106 (1948).
M. G. Krein, “Basic situation of the theory of representations of Hermitian operators with index defect (m, m),” Ukr. Mat. Zh.,1, No. 2, 3–66 (1949).
M. G. Krein, “On an application of the fixed point principle to the theory of linear transformations with indefinite metric,” Usp. Mat. Nauk,5, No. 2, 180–190 (1950).
M. G. Krein, “On applications of an algebraic proposition to the theory of monodromy matrices,” Usp. Mat. Nauk,6, No. 1, 171–177 (1951).
M. G. Krein, “Basic situation of the theory of λ-zones of stability of canonical systems of linear differential equations with periodic coefficients,” in: Memoirs of A. A. Andronov [in Russian], Izd. Akad. Nauk SSSR (1955), pp. 413–498.
M. G. Krein, “On integral representations of continuous Hermitian-indefinite functions with a finite number of negative squares,” Dokl. Akad. Nauk SSSR,125, No. 1, 31–34 (1959).
M. G. Krein, “On some new results in the theory of perturbations of linear operators (Abstract of Report),” in: Proceedings of the Fourth All-Union Mathematical Congress [in Russian], Vol. 1, Akad. Nauk SSSR, Leningrad (1963), pp. 133–134.
M. G. Krein, “On a new principle for applying a fixed-point method to the theory of operators in a space with indefinite metric,” Dokl. Akad. Nauk SSSR,154, No. 5, 1023–1026 (1964).
M. G. Krein, Lectures on the Theory of Stability of Solutions of Differential Equations in a Banach Space [in Russian], Kiev (1964).
M. G. Krein, “Introduction to the geometry of indefinite ℐ-spaces and the theory of operators in these spaces,” in: Second Summer Mathematics School [in Russian], Vol. 1, Kiev (1965), pp. 15–92.
M. G. Krein “Analytic problems and results of the theory of linear operators in a Hilbert space,” in: Proceedings of the International Congress of Mathematicians, 1966 [in Russian], Moscow (1968), pp. 189–216.
M. G. Krein, “On the disposition of the roots of polynomials, orthogonal on the unit circle with respect to alternating weights,” in: Theory of Functions, Functional Analysis, and Their Applications, Republican Scientific Compendium [in Russian], Vol. 2 (1966), pp. 131–137.
M. G. Krein and Yu. L. Daletskii, “On certain results and problems in the theory of stability of solutions of differential equations in a Banach space,” in: Proceedings of the Fifth International Conference on Nonlinear Oscillations [in Russian], Vol. 1, Kiev (1970), pp. 332–347.
M. G. Krein and H. K. Langer, “On spectral functions of a self-adjoint operator in a space with indefinite metric,” Dokl. Akad. Nauk SSSR,152, No. 1, 39–42 (1963).
M. G. Krein and H. K. Langer, “On the theory of quadratic bundles of self-adjoint operators,” Dokl. Akad. Nauk SSSR,154, No. 6, 1258–1261 (1964).
M. G. Krein and H. K. Langer, “On certain mathematical principles of the linear theory of damped oscillations of continua,” in: Proceedings of the International Symposium on Applications of Function Theory to the Mechanics of Continuous Media [in Russian], Vol. 2, Nauka, Moscow (1966), pp. 283–322.
M. G. Krein and H. K. Langer, “On defective subspaces and generalized resolvents of a Hermitian operator in a Πϰ space,” Funkts. Anal. Prilozhen.,5, No. 2, 59–71 (1971).
M. G. Krein and H. K. Langer, “On the indefinite degree moment problem,” Dokl. Akad. Nauk SSSR,226, No. 2, 261–264 (1976).
M. G. Krein and G. Ya. Lyubarskii, “On the theory of bands of transmission of periodic wave guides,” Prikl. Mat. Mekh.,25, No. 1, 24–37 (1961).
M. G. Krein and G. Ya. Lyubarskii, “On analytic properties of multipliers of periodic canonical differential systems of positive type,” Izv. Akad. Nauk SSSR, Ser. Mat.,26, No. 4, 549–572 (1962).
M. G. Krein and M. A. Rutman, “Linear operators, leaving invariant a cone in a Banach space,” Usp. Mat. Nauk,3, No. 1, 3–95 (1948).
M. G. Krein and Yu. L. Shmul'yan, “On a class of operators in a space with indefinite metric,” Dokl. Akad. Nauk SSSR,170, No. 1, 34–37 (1966).
M. G. Krein and Yu. L. Shmul'yan, “On plus-operators in a space with indefinite metric,” Mat. Issled.,1, No. 1, Kishenev, Akad. Nauk Mold. SSR, 131–161 (1966).
M. G. Krein and Yu. L. Shmul'yan, “ℐ-polar representation of plus-operators,” Mat. Issled.,1, No. 2, Kishenev, Akad. Nauk Mold. SSR, 172–210 (1966).
M. G. Krein and Yu. L. Shmul'yan, “On linear-fractional transformations with operator coefficients,” Mat. Issled.,2, No. 3, Kishenev, Akad. Nauk Mold. SSR, 64–96 (1967).
M. G. Krein and V. A. Yakubovich, “Hamiltonian systems of linear differential equations with periodic coefficients,” in: Proceedings of the International Symposium on Linear Oscillations [in Russian], Vol. 1, Kiev (1963), pp. 277–305.
S. G. Krein and N. N. Moiseev, “On the oscillations of a rigid body containing fluid with a free surface,” Prikl. Mat. Mekh.,21, No. 2, 169–174 (1957).
A. V. Kuzhel' (O. V. Kuzhil'), “Spectral analysis of quasiunitary operators of first rank in a space with indefinite metric,” Dopovidi Akad. Nauk Ukr. ESR, No. 5, 572–574 (1962).
A. V. Kuzhel', “Triangular model ofK 1-operators in a space with an indefinite metric,” Dopovidi Akad. Nauk Ukr. RSR, No. 5, 572–574 (1962).
A. V. Kuzhel', “Characteristic matrix functions of quasiunitary operators of any rank in a space with indefinite metric,” Dopovidi Akad. Nauk Ukr. RSR, No. 9, 1135–1138 (1962).
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Translated from Itogi Nauki i Tekhniki, Matematicheskii Analiz, Vol. 17, pp. 113–206, 1979.
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Azizov, T.Y., Iokhvidov, I.S. Linear operators in spaces with indefinite metric and their applications. J Math Sci 15, 438–490 (1981). https://doi.org/10.1007/BF01375563
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DOI: https://doi.org/10.1007/BF01375563