Calling all harmony-lovers. Crosby, Stills & Nash were a folk rock supergroup made up of musicians David Crosby, Stephen Stills, and Graham Nash (and sometimes Neil Young, making them Crosby, Stills, Nash & Young). This song showcases their harmonies quite well. (Note: if you’re in the mood for a more up-beat song from them, you can check out Suite: Judy Blue Eyes here).