Converse, Jean M., author
John Wiley & Sons, 1974
Buku Teks
Bryman, Alan, author
Oxford University Press, 2016
Buku Teks
edited, Bridget Somekh, Cathy Lewin
Sage Publications , 2005
Buku Teks
Johnson, John M., author
The Free Press, 1975
Buku Teks
Simon, Julian L.
Random House, 1978
Buku Teks