The Roud Folk Song Index is (to quote from its Wikipedia entry): "a database of nearly 200,000 references to nearly 25,000 songs that have been collected from oral tradition in the English language from all over the world"

While we already have a Series for this ( https://musicbrainz.org/series/4e817004-53ed-438e-96da-88e27fb8d872 ) it would be nice if we could (probably via a bot) add external links to the online copy of the index, here:

http://www.vwml.org/roudnumber/