A SIHR member had this. Hope it helps.
Here's a partial list -- I went out of the Rude Pravo archives and prior to the games of December 25, they didn't list referees for non-Czechoslovakia games.
Graham is listed on the refereeing teams for these games:
December 25, 1976 - Finland 4, West Germany 1
December 26, 1976 - Poland 2, USA 2
December 28, 1976 - Czechoslovakia 5, USA 2
January 2, 1977 - Czechoslovakia 4, Sweden 2
--- In firstname.lastname@example.org, NICOLE MOORE wrote:
> Hi there,
> My name is Nicole. My late father, William Blair "Dusty" Graham was an Ontario Hockey League referee and went to Czechoslovakia for the World Junior Hockey championship games. I believe it was the Dec 1976 and Jan 1977 game but have been unable to find any information on the referees of the game. I do not know who was playing, but I thought I was 4, which would be the correct timing of the game. Also from what I could find, this was the only game played in Czechoslovakia in the 70's which is when he went. Any help to corroborate this info would be greatly appreciated as we are trying to complete his obituary.
> Nicole Moore
> Sent from my iPhone