1
2
by Barfield
Published 1989
3
4
by Garrett
5
Published 1990
6
Published 1991
7
by Calabrese
Published 1991
8
by Leeming
Published 1993
9
by Songqiao
Published 1994
10
by Wilson
Published 1991
11
by O'Neill
Published 1987
12
by Kaplan
Published 1991
13
Published 1988
14
by Gernet
Published 1972
15
Published 1993
16
Published 1981
17
Published 1990
18
by Bonavia
Published 1982
19
20
by Jenner
Published 1992