Babbie, Earl, author
Thomson/Wadsworth, 2004
Buku Teks
edited by Gary R. Vandenbos
Sage, 1980
Buku Teks
Babbie, Earl, author
Wadsworth and Cengage Learning, 2013
Buku Teks
Babbie, Earl, author
Cengage Learning, 2016
Buku Teks
Laurene Vaughan
Bloomsbury Academic, 2017
Buku Teks