GG: Jazz?

[Thayer A <A.Thayer@rhbnc.ac.uk>]

I have an ancient music dictionary, from around the early 60's/late 50's
which has an intriguing but short comment under GG. I can't remember exactly
what it says but it is something along the lines of 'Canadian pianist. Has
done some jazz work'(?). Is there any truth in this? Although it at first
seems preposterous to think of GG playing Jazz, he seems a person of so many
contradictions that perhaps it is true. Does anybody know about this, or if
there are any unofficial recordings of him playing Jazz(!)?

Andrew

PS Does anyone know if there is an on-line store with a big range of sheet
music for sale (preferably one which caters for composers as obscure as
Feinberg and Liapunov)? I'd be grateful for help on this.