Summary: Remove broken link.
< There us a mupad elisp package available:
< * ftp://vh213601.truman.edu/pub/EMuPAD/mupad.el
Is a computer algebra system, available for educational and personal use at MuPAD. Only the Windows GUI is really proprietary, but nevertheless it is non-free.
See MuPACS for editing mode.
And perhaps a line on that I believe one needs a commercial license for commercial use – Duh!