Quark-Antiquark Pairing Induced by Instantons in QCD
  The quark-antiquark pairing due to the four-fermion direct coupling induced by the instantons in QCD is studied in the framework of the functional integral method. The integral equations for the order parameters are derived. Several classes of the solutions of these non-linear equations are considered in details. Their implications for the dynamical symmetry breakings are discussed 
N. V. Hieu, N. H. Son, N. V. Thanh and H. B. Thang (Institute of   Physics, Vietnam)