Götze, Heinz, author
Prestel, 1998
Buku Teks
Baring-Gould, Sabine, author
Longman, 1906
Buku Teks
general editor, H.R. Loyn
Thames and Hudson, 1991
Buku Referensi
Hoyt, Robert S., author
Harcourt, Brace & World, 1966
Buku Teks
Huizinga, Johan, author
New York: Doubleday, 1956
Buku Teks