1
2
by Weaver
Published 1948
3
by Spengler
Published 2002
4
by Schweitzer
Published 1987
5
by Boorstin
Published 1998
6
by Boorstin
Published 1993
7
8
9
by Lipson
Published 1993
10
by Tainter
Published 1988
11
12
by Winks
Published 1992
13
by Adler
Published 2006
14
by Burke
Published 1987
15
by Boorstin
Published 1983
16
by Freeman
Published 2002
17
by Husain
Published 1994
18
Published 1991
19
by Braudel
Published 1995
20
by Burke
Published 1987