Matrix integrals as Borel sums of Schur function expansions
  The partition function for unitary two matrix models is known to be a double KP tau-function, as well as providing solutions to the two dimensional Toda hierarchy. It is shown how it may also be viewed as a Borel sum regularization of divergent sums over products of Schur functions in the two sequences of associated KP flow variables. 
J. Harnad, A. Yu. Orlov