Flora, David B., author
Sage, 2018
Buku Teks
Cohen, Lillian, author
Prentice-Hall, 1955
Buku Teks
Nurul Lathifah, author
2017
UI - Skripsi (Membership)
Robinson, Paul W.
Harper & Row , 1979
Buku Teks
Solso, Robert L., 1933-, author
Boston, 2002
Buku Teks