1. Geodesic flows on compact Riemannian manifolds of negative curvature;Anosov,1967
2. Instability of dynamical systems with several degrees of freedom;Arnol'd;Sov. Math. Dokl.,1964
3. Ergodic Problems of Classical Mechanics;Arnol'd,1968
4. On Axiom A Diffeomorphisms;Bowen,1978