Mystery Photo

Even though I'm not a chess collector, I get a fair amount of email on the subject. I assume this is because of my ongoing series on Top eBay Chess Items by Price, last seen in First Chess Postcards in the World. I'm always happy to get this sort of mail, because I invariably learn something about chess history.

Recently I received a message related to a post from June 2012, titled 'A' Is for Alekhine's Autograph. The sender of the message was the seller of the item pictured in that post, and he sent me a couple of scans which I've reproduced below.

The top scan is a photo showing (left to right) players that I believe are Kashdan, Flohr, Alekhine, Pirc, and Stoltz. The bottom scan is the reverse side of the photo -- apparently a postcard -- showing signatures of the same five players (top to bottom with Pirc and Stoltz on the bottom line). The bottom scan also shows a pencilled notation 'Nice 31' over the names of the five players (in the same order as the top photo). The uppermost pencilled note says 'consultation tournament' in Dutch, followed by a reference that I can't decipher.

My correspondent, himself a knowledgeable collector, noted, 'Nice 1931 seems doubtful because the info about the consultancy games there do not match the autographs.' Alekhine, Flohr, and Stoltz played there, but I could find no mention of the other two. If this is true, where was the photo taken?

After a little digging I discovered that all five players were on different teams at the Prague 1931 Olympiad. Was this the source of the photo and autographs? Perhaps an astute visitor to this blog can provide additional information.