1
by Kotler
Published 1990
2
by Lovelock
Published 1990
3
Published 1992
4
by Willingham
Published 1993
5
6
by Slutsky
Published 1995
7
by Morse
Published 1994
8
9
10
by Foxall
Published 1994
11
Published 1992
12
by Birt
Published 2005
13
14
Published 1994
15
16
Published 2005
17
Published 1999
18
by Fleishman
Published 1993
19
20