A Format for Instantons and Their Characterizations
  A characterization of instanton contributions to gauge field theory is given. The dynamics of instantons with the gluon field is given in terms of 'classical' instanton contributions, i.e. on the same footing as tree amplitudes in field theory. This paramaterization depends on the kinematics of the local instanton operators and their coupling dependence. A primary advantage of this 'classical' formulation is that the weak-strong duality and its relations with the perturbative sector are possibly made more manifest. 
Gordon Chalmers