"Federal Music Project (Minn.)" . . . . . "The John J. Becker papers cover the breadth of his career, especially his most active period, from roughly 1920 to 1950." . . "Correspondence" . "Scores" . . . . "John J. Becker papers" . . "Manuscripts" . . . . . "Posters" . . . . . . . . . . .