edited by William Dodge Lewis, Henry Seidel Canby, Thomas Kite Brown
John C. Winston, 1942
Buku Referensi
Papalia, Diane E.
McGraw-Hill, 2001
Buku Teks
Merriam-Webster, 2004
Buku Referensi
Macmillan, 1994
Buku Referensi
Henderson, I. F.
Longman, 1975
Buku Referensi