1. P. Dombroski,On the geometry of the tangent bundle, J. Reine und Angew. Math., 210 (1962), 73–88.
2. A. Gray,Pseudo-Riemannian almost product manifolds and submersions. J. Math. and Mech., 16 (1967), 715–737.
3. B. O’Neill,The fundamental equations of a submersion, Michigan J. of Math., 13 (1966), 459–469.
4. S. Kobayashi andK. Nomizu,Foundations of differential geometry, Vol. 1, Interscience, New York 1963.
5. S. Sasaki,On the differential geometry of tangent bundles of Riemannian manifolds, Tohoku Math. J., 10 (1958), 338–354.