Here are The Pennywhistlers (founded by Ethel) singing the iconic "Shto Mi e Milo" (it was then regarded as Macedonian) in 1966, which has since become an anthem of unaccompanied / a cappella singers all over the world. My own groups of the 80s-90s loved singing it too. Pete Seeger's "Rainbow Quest" (this clip is taken from one of those Eps) was often 'removed' from YT, so it's good to see it up yet again!!