1. A formula for the spectral radius of an operator;Holmes, R. B.;Amer. Math. Monthly,1968
2. Differentiable dynamical systems;Smale, S.;Bull. Amer. Math. Soc.,1967
3. Monographies Internationales de Math\'{e}matiques Modernes;Arnold, V. I.,1967
4. Roughness of geodesic flows on compact Riemannian manifolds of negative curvature;Anosov, D. V.;Dokl. Akad. Nauk SSSR,1962