Graham, B. (1969). The challenge ; sermons from Madison Square Garden. Doubleday.
Lua i Stíl Chicago (17ú heag.)Graham, Billy. The Challenge ; Sermons from Madison Square Garden. Garden City: Doubleday, 1969.
Lua MLA (9ú heag.)Graham, Billy. The Challenge ; Sermons from Madison Square Garden. Doubleday, 1969.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.