An integral formulation of Yang-Mills on loop space
  It is proposed an integral formulation of classical Yang-Mills equations in the presence of sources, based on concepts in loop spaces and on a generalization of the non-abelian Stokes theorem for two-form connections. The formulation leads in a quite direct way to the construction of gauge invariant conserved quantities which are also independent of the parameterization of surfaces and volumes. Our results are important in understanding global properties of non-abelian gauge theories. 
L. A. Ferreira and G. Luchini
hep-th math-ph math.MP