On series solutions of Volterra equations
  We derive formulae for the calculation of Taylor coefficients of solutions to systems of Volterra integral equations, both linear and nonlinear, either without singularities or with singularities of Abel type and logarithmic type. We also obtain solutions to certain systems of Volterra equations of the first kind. In all cases except the case of logarithmic singularities, we obtain recursive formulae for the calculation of the Taylor coefficients. In certain cases, we give proofs of convergence and rigorous estimates of the radius of convergence. 
S. A. Belbas