Blum, Milton L.
Harper & Row, 1968
Buku Teks
Olexiy Y. Chebykin, Gregory Z. Bedny, Waldemar Karwowski
CRC Press, 2008
Buku Teks
edited by Peter Warr
Panguin Books, 1978
Buku Teks
Bass, Bernard M., editor
Allyn and Bacon, 1979
Buku Teks
Nicolson, Paula
MacMillan Education, 1986
Buku Teks