1
by Adler, Alfred
Published 1962
2
by Ziglar, Zig
Published 1997
3
by Covey, Stephen R.
Published 1994
4
5
Published 2006
6
by Rafi Harumin, 1982-
Published 2013
7
by Albrecht, Karl
Published 2007
8
9
by Somersall, Allen C.
Published 1997
10
by Somersall, Allen C.
Published 1997
11
12
13
Published 2006
14
by Khoo, Kheng-Hor, 1956-
Published 2006
15
by Hasan Muhd Hj. Al Khair
Published 2005
16
Published 1997
17
by Ziglar, Zig
Published 1998
18
by Griffin, Douglas, 1946 -
Published 2002
19
by Mohd. Daud Bakar,, Dr.,
Published 2018