Norton, Frank
Angus and Robertson, 1953
Buku Teks
Crawford, J.G., author
Stanford University Press , 1954
Buku Teks
Hally, M. Bernard Dette
Elsevier, 2009
Buku Teks
Sutton, K.C.T., author
Law Book, 1974
Buku Teks
Oxford University Press, 1994
Buku Teks