American Book Company, [1914]
Buku Referensi
Springfield, Massacuset : G.& C. Merriam Co., Publishers, 1948.
Buku Teks
Bolander, Donald O.
Lexicon Publication, 1993
Buku Referensi
Groiler
Grolier Incorporated, 1992
Buku Referensi
Merriam-Webster Inc., 1988
Buku Referensi