proposal for inserting non-text datas in internet messages

I saw a printed copy of a paper describing a proposal for inserting non-text
elements (pictures, application datas, music, animations, etc.) into internet
messages.
I'm very interested in that (I'm developing a message editor, and I would
include graphics and formatted-text capabilities in the MS Windows version 
of my editor). Where can I get the file to reprint the paper?
Please send me numeric addresses for ftp, since our computer has only a 
reduced /etc/hosts.
Thanks in advance.
Roberto Piola