Sansone, G., & Conti, R. (1964). Non-linear differential equations (Rev. ed.). Pergamon Press; [distributed in the Western Hemisphere by Macmillan, New York].

Sansone, Giovanni, and Roberto Conti. Non-linear Differential Equations. Rev. ed. Oxford, New York: Pergamon Press; [distributed in the Western Hemisphere by Macmillan, New York], 1964.

Sansone, Giovanni, and Roberto Conti. Non-linear Differential Equations. Rev. ed. Pergamon Press; [distributed in the Western Hemisphere by Macmillan, New York], 1964.