On the solutions of Knizhnik-Zamolodchikov system
  We consider the Knizhnik-Zamolodchikov system of linear differential equations. The coefficients of this system are rational functions. We prove that under some conditions the solution of KZ system is rational too. We give the method of constructing the corresponding rational solution. We deduce the asymptotic formulas for the solution of KZ system when $\rho$ is integer. 
Lev Sakhnovich