Bazhura B. P.
Investigation of a dynamical system in a neighborhood of an invariant toroidal manifold in the general case
Ukr. Mat. Zh. - 1994. - 46, № 10. - pp. 1399–1408
A dynamical system is studied in the neighborhood of an invariant toroidal manifold for the most general relationship between the dimensionality of the phase space and the dimensionality of the manifold.