edited by Steve Pile and Michael Keith
Routledge, 1997
Buku Teks
Herod, Andrew, author
Willey Black well, 2009
Buku Teks
Valentine, Gill, author
Prentice-Hall, 2001
Buku Teks
Barcus, Holly R., author
Routledge, 2018
Buku Teks
Short, John Rennie, author
Prentice-Hall, 2000
Buku Teks