Visit <http://support.wolfram.com/mathematica/systems/windows/general/latestfonts.html> to get the fonts:
Mathematica1b.ttf
Mathematica1mb.ttf
Mathematica1m.ttf
Mathematica1.ttf
Mathematica2b.ttf
Mathematica2mb.ttf
Mathematica2m.ttf
Mathematica2.ttf
Mathematica3b.ttf
Mathematica3mb.ttf
Mathematica3m.ttf
Mathematica3.ttf
Mathematica4b.ttf
Mathematica4mb.ttf
Mathematica4m.ttf
Mathematica4.ttf
Mathematica5b.ttf
Mathematica5mb.ttf
Mathematica5m.ttf
Mathematica5.ttf
Mathematica6b.ttf
Mathematica6mb.ttf
Mathematica6m.ttf
Mathematica6.ttf
Mathematica7b.ttf
Mathematica7mb.ttf
Mathematica7m.ttf
Mathematica7.ttf


To install the mathml fonts for Axiom you need to:

cd /usr/share/fonts
tar -zxf mathmlfonts.tgz
cd mathml
(copy the mathematics font files here)
ttmkfdir -c
/usr/sbin/chkfontpath -q --add .
fc-cache -f -v

(these commands are contained in the file FONTCMD).
Then, in Firefox, you need to change
 Edit->Preferences
and change the default font to Math1
