You have it to rights with that nomination, except that you omitted to include Stan's marvellous 'Mary Ellen Carter" in the same breath.
A few that resonate personally with me:
Kumbaya - Joan Baez Mr Tamborine Man - Mike McCellan (a superb Aussie songwriter who does this as his party piece) In The Depths of the Temple - Jussi Bjoerling & Robert Merrill Guantanamera - Pete Seeger (who else)