61
62
Published 1994
63
Published 1998
64
by Kreyszig, Erwin
Published 1999
65
by Stroud, K. A.
Published 1996
66
by Azar, Betty Schrampfer
Published 1999
67
by Lipsey, Richard G.
Published 1992
68
by Regan, Patrick E.
Published 2000
69
by Corriveau, Jean Paul
Published 1998
70
Published 1978
71
72
by Percy, Diana
Published 1989
73
by Hanly, Jeri R.
Published 1999
74
75
76
by Sloman, John
Published 1999
77
78
79
80
by Kotler, Philip
Published 1999