1
2
Published 2004
3
Published 2003
4
Published 2004
5
by Hara
Published 1997
6
7
by Liu
Published 1998
8
by Stockwell
Published 1993
9
Published 2002
10
by Abdullah Dahana
Published 2002
11
Published 2002
12
by Stuart-Fox
Published 2003
13
14
by Fitzgerald
Published 1973
15
by Latsch
Published 1984
16
by Campbell
Published 1971
17
Published 2004
18
Published 2015
19
by Lo
Published 1989
20
by Chemillier-Gendreau
Published 2006