Unsteady Stokes equations: Some complete general solutions
  The completeness of solutions of homogeneous as well as non-homogeneous unsteady Stokes equations are examined. A necessary and sufficient condition for a divergence-free vector to represent the velocity field of a possible unsteady Stokes flow in the absence of body forces is derived. 
A Venkatlaxmi, B S Padmavathi and T Amaranath