Well, this is a little confusing...
http://goo.gl/APwiEIt's a Canadian newspaper from Friday, June 16, 1967 (the same day as Day 1 of the Monterey Pop Festival) advertising the M&P's playing that Sunday, the 18th (the same day they performed at Monterey) at the The Paul Sauvé Arena in Montreal, Quebec. Clearly they did not perform in Quebec that night. Wonder what the deal was with this?