Pei, Mario A., author
J.B. Lippincott, 1965
Buku Teks
Eco, Umberto, author
Fontana, 1997
Buku Teks
Hankes, Elmer Joseph
The Hankes Foundation, 1992
Buku Teks
Encyclopaedia Britannica, Inc. ; Funk & Wagnalls Co., 1961
Buku Referensi
Bloomfield, Leonard, author
Holt, Rinehart and Winston, 1961
Buku Teks