Rowland, Benjamin
Penguin Books, 1967
Buku Teks SO
edited by Markus Hattstein, Peter Delius
Konemann, 2000
Buku Referensi
Rodley, Lyn
Cambridge University Press, 1999
Buku Teks SO
edited by George Ansell, Markus Hattstein, Peter Delius
H.F. Ullmann, 2010
Buku Referensi
Blair, Sheila S.
Yale University Press, 1994
Buku Teks SO