Janet Houser, Kathleen S. Oman, editor
Jones and Bartlett , 2011
Buku Teks
Jean V. Craig, Rosalind L. Smyth, editor
Elsevier, 2012
Buku Teks
Rubin, Allen, author
John Wiley & Sons, 2012
Buku Teks
Leger, A.S. St., author
Open UNiversity Press, 1999
Buku Teks
Brown, Brian, author
Open University Press, 2003
Buku Teks