1. Abraham, R., Marsden, J. E., and Ratiu, T. (1988). Manifolds, Tensor Analysis and Applications (Springer-Verlag, Berlin).
2. Kobayashi, S., and Nomizu, K. (1963). Foundations of Differential Geometry (Interscience, New York), vol. 1.
3. Palais, R. S. (1957). Mem. Amer. Math. Soc. 22.
4. Sussmann, H. J. (1973). Trans. Amer. Math. Soc. 180, 171.
5. Brickell, F., and Clark, R. S. (1970). Differentiable Manifolds (Van Nostrand, London)