Covariant almost analytic vector field on Q - Quasi umbilical   hypersurface of a Sasakian manifold
  In this paper we have studied the properties of covariant almost analytic vector field on Q - quasi umbilical hypersurface $M$ of a Sasakian manifold $\tilde M$ with $(\phi, g, u, v, \lambda)-$structure and obtained the scalars $\alpha$ and $\beta$ using $1 - form u, v$ covariant almost analytic for the hypersurface $M$ to be totally umbilical and cylindrical. 
Sachin Kumar Srivastava, Alok Kumar Srivastava and Dhruwa Narain
math.DG