Neuman, William Lawrence, 1950-
Allyn and Bacon, 2003
Buku Teks SO
Mikes Saks, Judith Allshop, editor
Sage, 2019
Buku Teks SO
Neuman, William Lawrence, 1950-
Allyn and Bacon, 2000
Buku Teks SO
Creswell, John W.
Sage Publication, Inc, 2003
Buku Teks SO
Neuman, William Lawrence, 1950-
Allyn and Bacon, 1994
Buku Teks SO