Catholic Church. Pope & Fremantle, A. J. (1963). The papal encyclicals in their historical context (5th (expanded ed.).). New American Library.
Lua i Stíl Chicago (17ú heag.)Catholic Church. Pope agus Anne Jackson Fremantle. The Papal Encyclicals in Their Historical Context. 5th (expanded ed.). N.Y.: New American Library, 1963.
Lua MLA (8ú heag.)Catholic Church. Pope agus Anne Jackson Fremantle. The Papal Encyclicals in Their Historical Context. 5th (expanded ed.). New American Library, 1963.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.