Gould, William B., IV
MIT Press, 1982
Buku Teks
Reuschlein, Harold Gill
St. Paul Minn, 1990
Buku Teks
Verhagen, H.L.E.
Martinus Nijhoff, 1995
Buku Teks
Anson, William R., Sir
Oxford University Press, 1930
Buku Teks
Nemeth, Charles P.
Jones and Bartlett, 2011
Buku Teks