On classical -matrix for the Kowalevski gyrostat on .
On classical series expansions for quasi-periodic motions.
On implicit Lagrangian differential systems
Let (P,ω) be a symplectic manifold. We find an integrability condition for an implicit differential system D' which is formed by a Lagrangian submanifold in the canonical symplectic tangent bundle (TP,ὡ).
On isomorphism of integrable cases of the Euler equations on the bi-Hamiltonian manifolds and .
On Picard-Fuchs type equations related to integrable Hamiltonian systems.
On singularities of Hamiltonian mappings
The notion of an implicit Hamiltonian system-an isotropic mapping H: M → (TM,ω̇) into the tangent bundle endowed with the symplectic structure defined by canonical morphism between tangent and cotangent bundles of M-is studied. The corank one singularities of such systems are classified. Their transversality conditions in the 1-jet space of isotropic mappings are described and the corresponding symplectically invariant algebras of Hamiltonian generating functions are calculated.
On the Birkhoff normal form of a completely integrable hamiltonian system near a fixed point with resonance
On the existence of equations of evolution.
On the topology of an integrable variant of a nonholonomic Suslov problem