David, Rene, 1906-
Stevens & sons, 1985
Buku Teks
Erades, Judge
Martinus Nijhoff Publishers, 1983
Buku Teks
Fox, James R.
Oceana Publication, 1992
Buku Referensi
Roux, Theunis
Cambridge University Press, 2018
eBooks
Ehrmann, Henry W.
Prentice-Hall, 1976
Buku Teks