Ebbels, R.N., author
Landsdowne Press, 1965
Buku Teks
Turner, Ian, author
Hale & Iremonger, 1979
Buku Teks
Dhanani, Shafiq, author
Routledge, 2009
Buku Teks
Kluwer Academic Publishers, 1976
Buku Teks
editorial board, Benjamin Aaron, Thilo Ramm, Tore Sigeman, Jean -Maurice, Werdier
Martinus Nijhoff Publishers, 1992
Buku Referensi