Pilling, David, author
Tim Duggan Books,, 2018
Buku Teks
Russell, James S., author
Island Press, 2011
eBooks
Smith, Adam, author
Modern Library, 2000
Buku Teks
Smith, Adam, author
David Campbell Publishers, 1991
Buku Referensi
Cuervo, Jorge, author
ATD Press, 2015
Buku Teks