Yildirim M.Esin E.2020-06-252020-06-25200000472468https://doi.org/10.1007/BF01237476https://hdl.handle.net/20.500.12587/1648In this paper, the differential geometry of second canonical extension 2M of a differentiable manifold M is studied. Some vector fields tangent to 2M in TTM are determined. In addition we obtain that the second canonical extensions of M and a totally geodesic submanifold in M are totally geodesic submanifolds in TTM and 2M respectively. © Birkhauser Verlag, 2000.eninfo:eu-repo/semantics/closedAccessArticle691-2737810.1007/BF012374762-s2.0-52849089111Q3