Intersecting D-brane states derived from the KP theory
  A general scheme to find tachyon boundary states is developed within the framework of the theory of KP hierarchy. The method is applied to calculate correlation function of intersecting D-branes and rederived the results of our previous works as special examples. A matrix generalization of this scheme provides a method to study dynamics of coincident multi D-branes. 
Hironori Yamaguchi, Satoru Saito