Newtonian perturbations and the Einstein-Yang-Mills-dilaton equations
  In this paper we show that problem of proving the existence of a countable number of solutions to the static spherically symmetric SU(2) Einstein-Yang-Mills-dilaton (EYMd) equations can be reduced to proving the non-existence of solutions to the linearized Yang-Mills-dilaton equations (lYMd) satisfying certain asymptotic conditions. The reduction from a non-linear to a linear problem is achieved using a Newtonian perturbation type argument. 
Todd Oliynyk