Harrisson, Tom
Cornell University, 1969
Buku Teks SO
Hose, Charles, 1863-1929
Oxford University Press, 1993
Buku Teks
Wilson, Daniel
Cambridge University Press, 2015
eBooks
Mackinnon, John Ramsay
[publisher not identified], [date of publication not identified]
Buku Teks
Robinson, Danielm
Lonely Publications Pty Ltd, 2011
Buku Referensi