Non-existence of solutions for non-autonomous elliptic systems of   Hamiltonian type
  We extend the classical Pohozaev's identity to semilinear elliptic systems of Hamiltonian type, providing a simpler approach, and a generalization, of the results of E. Mitidieri [6], R.C.A.M. Van der Vorst [14], and Y. Bozhkov and E. Mitidieri [1]. 
Philip Korman
math.AP