Comment on "Convection in a horizontal fluid layer under an inclined   temperature gradient" [Phys. Fluids 23, 084107 (2011)]
  Ortiz-P\'erez and D\'avalos investigated the stability of parallel convective flow. From the article it seems that this equations of flow obtained by the authors. Meanwhile, it is well studied theoretically and experimentally(exact solution obtained more than half a century ago. 
Albert Sharifulin
physics.flu-dyn