Simpson, Sally S.
Cambridge University Press, 2002
Buku Teks
Stone, Christopher D.
Harper & Row , 1975
Buku Teks
edited by V.A.C. Gatrell, Bruce Lenman, and Geoffrey Parker
Europa Publications, 1980
Buku Referensi
Slapper, Gary, author
Longman , 1999
Buku Teks
Innes, Martin
Oxford Univesity Press, 2014
Buku Teks