Dual solutions of Yang-Mills field theories in Minkowski space
  Using spherical ansatz, we construct dual equations for non-abelian gauge fields in Minkowski space. The analytically continued instanton is shown to satisfy the dual equations but assumes a more ansatz. It is not the solution of MIT second order differential equation. The symmetries of the solution function space are examined. The relevant physics is reviewed. 
Liang-Xin Li and Bing-Lin Young