1
2
by Maznah Hamid, Datuk, 1955-
Published 2002
3
by De Bono, Edward, 1933-
Published 1986
4
by Cypert, Samuel A.
Published 1994
5
by Covey, Stephen R.
Published 1991
6
by Covey, Stephen R.
Published 1992
7
by Chu, Chin-Ning
Published 1994
8
by Maznah Hamid, Datuk, 1955-
Published 2004