Morse index and deformations of Hamiltonian systems
English version (Springer): Ukrainian Mathematical Journal 36 (1984), no. 4, pp 338-343.
Citation Example: Bondarchuk V. S. Morse index and deformations of Hamiltonian systems // Ukr. Mat. Zh. - 1984. - 36, № 4. - pp. 421 – 427.
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