21
by ANGIOLILLO
Published 1979
22
by PERRY
Published 1986
23
24
by KOLCHIN
Published 1987
25
by KEMP
Published 1990
26
by SLOAN
Published 1995
27
by ROSENSTONE
Published 1990
28
by YONEKURA
Published 1994
29
by HALPERIN
Published 1997
30
Published 1998
31
by VALLONE
Published 1995
32
by FOLSOM
Published 1991
33
34
by ROSENZWEIG
Published 1993
35
by SINN
Published 1992
36
by SELVAKUMARAN Ramachandran
Published 1994
37
by HIMMELFARB
Published 1995
38
Published 2007
39
Published 1997
40
by LEWIS
Published 1993