Pollit, Christopher
Oxford University press, 2000
Buku Teks
Edited by: Paul J. Andrisani, Simon Hakim, E.S. Savas
Kluwer Academic, 2002
Buku Teks
Lane, Jan-Erik
Routledge, 2000
Buku Teks SO
Artikel Jurnal
Mark Bovens, Paul't Hart, B. Guy Peters
Edward Elgar Publishing, Inc, 2001
Buku Teks