edited by Kevin Gilmartin
Cambridge University Press, 2017
Buku Teks
edited by George R. Creeger and Joseph W. Reed, Jr.
Holt, Rinehart and Winston, 1964
Buku Teks
Weatherill, Lorna
Routledge, 1996
Buku Teks
Cherry, Deborah, author
Routledge, 2000
Buku Teks
Massey, Anne, author
Manchester University , 1995
Buku Teks