1
Published 1997
2
Published 1997
3
Published 1997
4
by Strugnell, Lynne
Published 2000
5
by Lerman, Paul
Published 1990
6
7
by SCHWARZ, Edward A.
Published 1988
8
9
10
by Covey, Stephen R
Published 1991
11
by Hopkins, Tom
Published 1979
12
13
by Provenzano, Steven
Published 1995
14
by Lawrence, Judy
Published 1993
15
by Nik Eliani Nik Nawi
Published 2000
16
17
by Buzan, Tony
Published 1991
18
19
by Elgin, Suzette Haden
Published 1991
20
by Chopra, Deepak
Published 1990