A February 1977 postcard from Dick Higgins to Steve McCaffery, from the Granary Books Steve McCaffery Archive.
The card reads:
"Dear Steve -
Karl Young wants to look at the Filliou/bpN/SMcC/dh book when it's ready for his Membrane Press - okay?
Love to you and Maggie, & to bp,
The book Higgins refers to is called Six Fillious, and is co-authored by Filliou, Higgins, McCaffery, bpNichol, George Brecht and Dieter Roth. See earlier post, here, for details.