That was from the online Roud index. I have my own copy of Roud but it hasn't been updated for a long time (although I think when I bought it it was supposed to have free updates; but when we moved I never notified Steve, so it's not surprising!). I have it in Access on my old XP machine, but I also converted it to a Prolog database which is what I used on my current Ubuntu machine. I can do more tailor made searches on the Prolog database (it would also have made your project for canonical titles easy to do).

Mick