Tommy Sands and Dolores Keane of Ireland recorded "Where have all the Flowers Gone" along with an instrumental interlude of "'S é fath mo bhuartha" (Irish air/song). I don't know who the additional instrumentalists were. I heard it last night on "Folk Club" presented by Tony McAuley on BBC Radio Ulster (Northern Ireland) -- may be available on line at BBC website. Tony said that Pete Seeger the tune for the song from the Irish air. To me, 'S é fath mo bhuartha stood out as a distinct tune. What does Pete Seeger say about his musical inspiration?
I see Teru says the tune is Ukranian