editor, Rom Harre, Roger Lamb
Blackwell Reference, 1983
Buku Referensi
South, David W., author
McGraw-Hill , 1995
Buku Referensi
De Vries, Mary Ann, author
[Publisher not identified], 1978
Buku Teks
De Vries, Mary Ann, author
Prentice-Hall, 1995
Buku Referensi
Douglas-Young, John, author
Prentice-Hall, 1983
Buku Referensi