Eisenstadt, Shmuel Noah
The Political systems of empires
Free Press, 1967
Buku Teks
Eisenstadt, Shmuel Noah
The political system of empires
Free Press, 1969
Buku Teks
Easton, David
A systems analysis of political life
John Wiley & Sons, 1965
Buku Teks
Maor
Political Parties & Party Systems
Buku Teks
Political systems and the distribution of power
edited by Michael Banton
Tavistock Publications, 1972
Buku Teks