Davis, Jack, author
Currency, 1986
Buku Teks
Heijbroek, A.M.A., author
Rabobank International Group, [Date of publication not identified]
Buku Teks
Jolley, Elizabeth, author
Fremantle Arts Centre Press, 1988
Buku Teks
Chen, James C. P., author
Wiley, 1985
Buku Referensi
Marianne Wait, editor
Reader's Digest, 2007
Buku Teks