Punch, Keith F., author
SAGE Publications, 1998
Buku Teks
edited by Christina Hughes
Open University Press, 2003
Buku Teks
Gillham, Bill, author
Open University Press, 2008
Buku Teks
Smith, Joan Macfarlance
Routledge & K. Paul, 1972
Buku Teks
Lee, Ann Fuji, author
Routledge, Taylor & Francis Group, 2018
Buku Teks