Color Confinement in lattice Landau gauge with unquenched Wilson and KS   fermions
  The Kugo-Ojima confinement criterion is verified in the unquenched Landau gauge QCD simulation. The valence quark propagator of the Kogut-Susskind fermion with use of the fermion action including the Naik term and the staple contribution is calculated on MILC Asqtad unquenched gauge configurations, and it shows infrared suppression of the quark propagator. 
Hideo Nakajima and Sadataka Furui