Tierney, Kevin, author
Oceana Publication, 1971
Buku Teks
Buku Teks
Dowling, Tim, 1963-, author
Fourth Estate, 2015
Buku Teks
Blaxter, Loraine, author
Open University Press , 1996
Buku Teks
Roman, Kenneth, author
Elex Media Komputindo, 2005
Buku Teks