Priestley, J. B. (John Boynton), 1894-1984, author
Harper, 1960
Buku Teks
Keene, Donald, author
Grove Press, 1955
Buku Teks
Keene, Donald, author
J. Murray, 1953
Buku Klasik
editor in chief, Mortimer J. Adler
Encyclopedia Britanica, 1990
Buku Referensi
editor in cheief, Mortimer J. Adler
Encyclopedia Britanica, 1996
Buku Referensi