Cambridge University Press, 2020
eBooks
Schulz, Ernest B
[publisher not identified], 1956
Buku Teks
Arblaster, Anthony, author
Open University Press, 1987
Buku Teks
Artikel Jurnal
Eisenstadt, S. N. (Shmuel Noah), author
The Woodrow Lilson Center Press, 1999
Buku Teks