MATHEMATICA SCANDINAVICA, vol.102, no.2, pp.253-264, 2008 (SCI-Expanded)
In this paper, We Study lightlike hypersurfaces of a semi-Riemannian manifold admitting a semisymmetric non-metric connection. We give the equations of Gauss and Codazzi. Then, we obtain conditions under which the Ricci tensor of a lightlike hypersurface is symmetric given that the ambient space is equipped with a semi-symmetric non-metric connection.