Certain invariant submanifolds of generalized Sasakian-space-forms

In the present paper we initiate the study of invariant submanifolds of generalized Sasakian-space-forms with K-contact metric. We consider pseudo-parallel and generalized Ricci pseudo-parallel invariant submanifolds of generalized Sasakian-space-forms. Also we characterize invariant submanifolds whose second fundamental form satisfies some restrictions with respect to concircular curvature tensor of the ambient manifold. Finally, we give some examples of invariant submanifolds of generalized Sasakian-space-forms to verify our results.