GUEST,
What do you want to do with it? The only problem arises if you want to do something commercial with it. If it was published in a book you are allowed to use a certain percentage of the book's content for educational purposes, say in a thesis. People rip off trad material all the time and very seldom is anyone sued. It is customary and good practice to credit your sources. I always try to do this. Broadsides themselves prior to 1938 can't be copyrighted as they are all out of copyright and no-one now has the right to copyright them so they are in the pd. If you are still worried try contacting the publishers.

I'm no legal expert. I'm just referring to general practice here.