edited by Michael Eid and Ed Diener
American Psychological Association, 2006
Buku Teks
John Wiley & Sons, 2003
Buku Teks SO
Morgan, David, author
International Engineering Consortium, 2007
eBooks
editor, John G. Webster
CRC Press, 1999
Buku Referensi
Morgan, David, author
Peter Peregrinus, 1996
Buku Referensi