1
by Athukorala, Premachandra
Published 2001
2
Published 2000
3
Published 1991
4
by Masson, Paul R.
Published 1990
5
Published 1997
6
7
Published 2000
8
Published 2003
9
Published 1998
10
Published 1991
11
Published 1996
12
by Mathieson, Donald J.
Published 1993
13
by Woodward, David
Published 2001
14
by George, Robert Lloyd
Published 1992
15
Published 2001
16
Published 1996
17
by Varman-Schneider, Benu
Published 1991
18
by Athukorala, Prema-chandra
Published 2001
19
Published 1990
20