Singular solutions of Yang-Mills equations and bag model
  A model of quark confinement based on a singular solution of classical YM equation is proposed. Within the framework of this model we have calculated hadron masses that correspond to ground state configurations of quarks. Our results are in agreement with the experiment data with accuracy 3-7 percents for all hadronic masses except those of light pseudoscalar mesons. 
F.A. Lunev and O.V. Pavlovsky