Maple, James
John Murray, 1996
Buku Teks
Clough, Peter
Sage Publications, 2002
Buku Referensi
Yoshino, Kosaku
Routledge , 1992
Buku Teks
Koen Vermeir
Springer, 2012
eBooks
Rivers, W. H. R. (William Halse Rivers), 1864-1922
The Athlone Press, 1968
Buku Teks