Assassin’s Creed

First time playing through AC: Revelations after 100%-ing the first 3 games and I can't seem to find all the Animus Data Fragments. When I hit 50, it gave me a message that they've been unlocked on the map but I'm at 92 collected and there are no more shown on the map. Is this a bug? Did I miss a few early ones or something? I'd rather not have to go through a guide online and check if I got every single one by going to each spot one at a time.