Williams, Robert, author
Gower, 1991
Buku Teks
Robertson, Hector Menteith, author
Cambridge University Press, 1957
Buku Teks
Laode M Syarif, author
Komisi Pemberantasan Korupsi, 2019
Artikel Jurnal
edited by John A. Wiseman
Routledge, 1995
Buku Teks
Murdock, George Peter, author
McGraw-Hill, 1959
Buku Teks