1
by MacKinnon
Published 2009
2
by Thiroux
Published 2010
3
by Pojman
Published 2011
4
by ROSENSTAND
Published 2000
5
by VARDY
Published 1994
6
by MacKinnon
Published 2001
7
by HARRIS
Published 2002
8
by Thiroux
Published 2001
9
by Pence
Published 2007
10
by MacKinnon
Published 2012
11
by Timmons
Published 2002
12
by WAIN
Published 1995
13
by ARISTOTLE
Published 1985
14
by AGIUS
Published 1994
15
by Williams
Published 1985
16
by BARRY
Published 1991
17
by VAN DER STEEN
Published 1995
18
by RICHARDS
Published 1971
19
by ARISTOTLE
Published 1976
20
by ELFORD
Published 2000