INTERNATIONAL ELECTRONIC JOURNAL OF GEOMETRY, cilt.9, sa.1, ss.70-77, 2016 (ESCI)
In the present paper we give conditions for screen semi invariant lightlike submanifolds of a semi-Riemannian product manifold to have degenerate planar normal sections. Also we give sufficient and efficient conditions for screen invariant and screen anti invariant lightlike submanifold of a semi-Riemanniann product manifold to have non-degenerate planar normal sections.