CSNY are touchstones for classic-rock and alternative artists rooted in folksy songcraft. While their breezy style suffuses the Eagles' mellow L.A. country rock in “Peaceful Easy Feeling,” their sky-high voices echo throughout the dreamy indie folk of Fleet Foxes' “White Winter Hymnal.” Crosby and Nash even lend smooth harmonies to protégé Jackson Browne's gospel-touched ballad “Jamaica Say You Will.”