Bracy, Warren D.
The Bobbs-Merrill Company, Inc., 1978
Buku Teks
Dyer, Justin Buckley, author
Cambridge University Press, 2013
eBooks
Rubenstein, William, author
West A Tomson Reuters Busines, 2011
Buku Teks
Davies, Jack, author
West Publishing, 1975
Buku Teks
Wood, William
Percival Marshall, 1949
Buku Teks