Bevan, Vaughan
Butterworth, 1991
Buku Teks
Shah, Giriraj
Anmol Publications PVT. Ltd., 1999
Buku Referensi
Dutelle, Aric W.
Jones and Bartlett Publishers, 2011
Buku Teks
Manurung, Binsar Daniel H.
Universitas Indonesia, 2011
UI - Tesis Open
Smart, Huw
Oxford University Press, 2006
Buku Referensi