Nesfield, J.C.
MacMillan Press , 1978
Buku Teks
Rochemont, Michael S.
Cambridge University Press, 1993
Buku Teks
Surenne, Gabriel
Oliver and Boyd, [date of publication not identified]
Buku Referensi
Tomasowa, Francien Herlen
Universitas Brawijaya , 2005
Buku Teks
Tomasowa, Francien Herlen
Universitas Brawijaya, 2005
Buku Teks