Higher order mean curvatures of SAC half-lightlike submanifolds of   indefinite almost contact manifolds
  We introduce higher order mean curvatures of screen almost conformal (SAC) half-lightlike submanifolds of indefinite contact manifolds, admitting a semi-symmetric non-metric connection, and use them to generalize some known results of [6]. Also, we derive a new set of integration formulae via the divergence of some special vector fields tangent to this submanifold. Several examples are also included to illustrate the main concepts. 
Fortun\'e Massamba and Samuel Ssekajja
math.DG