1. Sopra le funzioni che dipendono de altre funzioni;Volterra;Rend R. Academia dei Lincei 2 Sem,1987
2. Theory of Functionals and Integral and Integral Differential Equations;Volterra,1959
3. Nonlinear Problems in Random Theory;Wiener,1958
4. The Use of functionals in the analysis of nonlinear physical systems;Barrett;Journal of Electronics and Control,1963