1. Bourbaki, N.: Variétés différentielles et analytiques, Fasc. rés §. 1-7. Paris: Hermann 1967
2. Blumenthal, R.A., Hebda, J.J.: The generalized Cartan-Ambrose-Hicks theorem. C.R. Acad. Sci., Paris, Sér.I 305, 647–652 (1987)
3. Chevalley, C.: Theory of Lie groups, vol. 1, Princeton: Princeton University Press 1946
4. Dombrowski, P.: Differentialgeometrie III, unpublished. Lectures at University of Cologne (1987/88)
5. Greub, W., Halperin, S., Vanstone, R.: Lie groups, principal bundles, and characteristic classes, vol. 2. New York London: Academic Press 1973