1. S. Aizicovici,Note on an abstract Volterra equation, An. Şti. Univ. “Al. I. Cuza” Iaşi Sect I a Mat.23 (1977), 87–92.
2. V. Barbu,Nonlinear Semigroups and Differential Equations in Banach Spaces, Noordhoff International Publishing, 1976.
3. V. Barba, On a nonlinear Volterra integral equation on a Hilbert space, SIAM J. Math. Anal.8 (1977), 345–355.
4. Ph. Clement,On abstract Volterra equations with kernels of positive resolvent, to appear.
5. M. G. Crandall and T. Liggett,Generation of semigroups of nonlinear transformations on general Banach spaces, Amer. J. Math.93 (1971), 265–298.