Walker, Warren F.
Saunders College Pub., 1986
Buku Referensi
Gadow, Hans, 1855-1928, author
Cambridge University Press , 2014
Buku Teks
Bentley, P.J.
Cambridge University Press, 1982
Buku Teks
edited by David Sedmera, Tobias Wang
Springer, 2012
eBooks
Young, J.Z.
At The Clarendon Press, 1962
Buku Teks