Graham, B. (1983). Approaching hoofbeats: The four horsemen of the apocalypse. Word.
Lua i Stíl Chicago (17ú heag.)Graham, Billy. Approaching Hoofbeats: The Four Horsemen of the Apocalypse. Waco: Word, 1983.
Lua MLA (9ú heag.)Graham, Billy. Approaching Hoofbeats: The Four Horsemen of the Apocalypse. Word, 1983.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.