Taylor, Neil
Sense, 2012
eBooks
edited by Arlene J. Lowenstein, Lynn Foord-May, Jane C. Romano
Jones and Bartlett, 2009
Buku Teks
Russell, Robert D.
National Education Association, 1975
Buku Teks
editor, Spyros Doxiadis; editorial committee, Alastair Campbell V....[et al.]
John Wiley & Sons, 1990
Buku Teks
Kimbrough, Vickie J., author
Pearson, Prentice Hall, 2006
Buku Teks