Kershaw, Baz
Routledge, 1992
Buku Teks SO
Simpson, Leanne, 1971-
University of Minnesota Press, 2017
Buku Teks SO
Mackay, James
Longman , 1984
Buku Teks SO
Commager, Henry Steele
Dodd, Mead, 1965
Buku Teks SO
Hanbury, Harold Grenville
Methuen, 1956
Buku Teks