Jolley, Elizabeth
Fremantle Arts Centre Press, 1988
Buku Teks SO
Heijbroek, A.M.A.
Rabobank International Group, [Date of publication not identified]
Buku Teks SO
Chen, James C. P.
Wiley, 1985
Buku Referensi
Marianne Wait, editor
Reader's Digest, 2007
Buku Teks SO
Bogaards, Carla
De Bezige Bij, 1990
Buku Teks