41
Published 1985
42
43
by Shade, E.D.
Published 1990
44
Published 1992
45
46
Published 1994
47
by Pindyck, Robert S.
Published 1995
48
49
by Collier, Barry
Published 1995
50
by Ellis, Elizabeth
Published 1988
51
52
53
54
55
by Gibson, Andrew
Published 1997
56
57
58
by Mclennan, W.
Published 1995
59
by Poole,Jill
Published 1992
60