Barone, Michael, author
National Journal, 1992
Buku Referensi
Barone, Michael, author
National Journal, 1990
Buku Referensi
Mackie, Thomas T., author
Facts on File, 1982
Buku Referensi
Buttazzo, Giuseppe, editor
[Springer, ], 2012
eBooks
Senson, Ben, author
Delmar Cengage Learning, 2011
Buku Teks