Heringa, A.W.
Metro, 2009
Buku Teks
Strong, C.F.
Sidgwick & Jackson Limited, 1960
Buku Teks
Strong, C.F.
Sidgwick and Jackson, 1972
Buku Teks
edited by Eivind Smith
Kluwer Law International, 1995
Buku Teks
Wells, S.J.
Cambridge University Press , 1964
Buku Teks