Mueller, Dennis C., author
Cambridge University Press, 2005
Buku Teks
Dunleavy, Patrick
N.Y. Harvester , 1991
Buku Teks
Udehn, Lars, author
Routledge, 1996
Buku Teks
Gwartney, James D., author
The Reyden Press, 2000
Buku Teks
Dunleavy, Patrick
Havester Wheatsheaf, 1991
Buku Teks