Jackson, W. (1998). The four ages: Together with essays on various subjects. Thoemmes.
Lua i Stíl Chicago (17ú heag.)Jackson, William. The Four Ages: Together with Essays on Various Subjects. Bristol: Thoemmes, 1998.
Lua MLA (8ú heag.)Jackson, William. The Four Ages: Together with Essays on Various Subjects. Thoemmes, 1998.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.