Folk music - anthologies

Folk Song USA: The 111 Best American Ballads. Collected, adapted, and
arranged by John A. Lomax and Alan Lomax. Charles Seeger and Ruth 
Crawford Seeger, music editors. NY: Duell, Solan and Pearce, 1947.

Lomax, Alan. The Folk Songs of North America in the English Language.
Garden City, NY: Doubleday & Co., 1960.