Boss, Judith A., author
McGraw-Hill, 2004
Buku Teks
Tiles, J.E., author
Routledge, 2000
Buku Teks
Robinson, Simon, 1951-,author
Jessica Kingsley Publishers, 2008
Buku Teks
Downie, R.S
Oxford University Press, 1994
Buku Teks
State University of New York Press, 1970
Buku Teks