Butler, William J.
International Commission of Jurists, 1977
Buku Teks
Nadeak, Kustigar, author
Pustaka Sianar Harapan, 1986
Buku Teks
Phelan, John Leddy, author
University of Wisconsin Press, 1959
Buku Teks
Reed, Robert Ronald
The University of Manila , 1967
Buku Teks
La Gironiere, Paul P.De
Buku Teks