G language

I recently saw a 1993 article about a 4th generation language called G,
which would serve as an intermediairy between GRASS and expert systems.
Could someone point me at sources of information about that language?
FTP sites, WEB-sites? I have searched but couldn't find anything on the
GRASS pages.

I am planning to write an expert system in CLIPS, which would query
GRASS files. Could I link CLIPS with G?

Thanks for helping me out!! Luc