Schuck, Peter H., author
Oxford University Press, 1994
Buku Teks
Brown, L. Neville (Lionel Neville), author
Clarendon Press, 1998
Buku Teks
Lorch, Robert S., author
Wayne State University Press, 1969
Buku Teks
Tracey, Richard R.S., author
Butterworth, 1975
Buku Teks
Scheb, John M., author
Thomson Wadworth, 2005
Buku Teks