Brown, Craig
Carswell, 1995
Buku Teks
Dobbyn, John F., author
West Publishing, 1989
Buku Teks
Bruce D. Mudget [and others]
Alexander Hamilton Institute, 1962
Buku Teks
Mowbray, Albert H.
McGraw-Hill, 1955
Buku Teks
Eggers, Peter MacDonald, author
Routledge, 2018
Buku Teks