Fox, James R.
Oceana Publication, 1992
Buku Referensi
Gutteridge, H. C.
Cambridge University Press, 1949
Buku Teks
Ehrenzweig, Albert A.
Leiden A.W. Sijthoff 1973,
Buku Teks
Faculty of Law National University of Singapore, 2018
Majalah, Jurnal, Buletin
Cambridge University Press, 2019
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