Babbie, Earl, author
Wadsworth and Cengage Learning, 2013 (Student Edition)
Buku Teks
Babbie, Earl, author
Wadsworth and Cengage Learning, 2013 (International edition)
Buku Teks
May, Tim, author
Open University Press, 2001
Buku Teks
Judd, Charles M., author
Methuen, 1991
Buku Teks
Sjoberg, Gideon
Harper & Row Publishers, 1968
Buku Teks