1
by Wukovits
Published 2001
2
by Arora
Published 2005
3
by D. Jain
Published 2005
4
by Liebman
Published 1996
5
by Twist
Published 2007
6
by Corsi
Published 2002
7
Published 1991
8
by Miller
Published 2003
9
by Powell
Published 2009
10
by Twist
Published 1997
11
by Walte
Published 2010
12
by Johnstone
Published 2001
13
Published 2015
14
Published 2007
15
by Olney
Published 1982
16
Published 1981
17
18
Published 1998
19
Published 1998
20
by Oggiss
Published 1986