Marsden, William, author
Oxford University Press, 1984
Buku Referensi
Dreyer, Hilke, author
Verlag fur Deutsch , 1994
Buku Teks
Visser, Leontien E., author
Foris Publications, 1987
Buku Referensi
Wandelt, Ingo, author
Friedrich Ebert Stiftung Indonesia Office, 2009
Buku Referensi
Miell, Anna, author
Routledge, 2006
Buku Teks