Masannat, George S.
The American political system: introductory readings
Charlies Scribuner's Sons, 1971
 Buku Teks SO
Cummings, Milton C.
Democracy under pressure: an introduction to the American political system
Harcourt Brace Jovanovich, 1977
 Buku Teks SO
Cummings, Milton C.
Democracy under pressure: an introduction to the American political system
Harcourt Brace Jovanovich, 1981
 Buku Teks SO
Wallace, Iain
The global economic system / Iain Wallace
Routledge , 1990
 Buku Teks SO
Political parties and electoral change : party responses to electoral markets
Sage Publications, 2004
 Buku Teks SO