I bought one of the pix sleeve 45s almost by accident. I was at the long-vanished Tower Records in West Covina CA and asked if the "Trio" LP was out yet. The clerk said, "Not until next week, but we have the single" and pointed me to the 45. I was rather surprised to see a late-50s pop number, because I understood that the track list for the LP was "old timey", but I checked the fine print and yep, it was the Phil Spector song. I remember reading in a 1979 book about Linda that mentioned the three singers wanting to collaborate, but between busy schedules and being on different labels, it took several years to bring the idea to reality.