Ingersoll, D. (1991). Philosophic roots of modern ideology (2nd ed.). Prentice-Hall.
Lua i Stíl Chicago (17ú heag.)Ingersoll, D. Philosophic Roots of Modern Ideology. 2nd ed. New Jersey: Prentice-Hall, 1991.
Lua MLA (9ú heag.)Ingersoll, D. Philosophic Roots of Modern Ideology. 2nd ed. Prentice-Hall, 1991.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.