1
2
Published 1991
3
Published 2007
4
Published 2006
5
6
7
Published 2006
8
Published 1991
9
Published 1992
10
by Hofstadter, Richard
Published 1979
11
by Fisher, Louis
Published 1981
12
Published 1989
13
Published 1991
14
by Lindsay, James M.
Published 1994
15
by Abramson, Paul R.
Published 1990
16
Published 1993