Musgrove, a British poet with a collection of Outsider Art (the outsider archive) writes about Adolf Wolfli: "It is also of particular importance that Wolfli was ahead of everybody - he invented collage combinations with painting around the turn of the century, included a Campbell soup can in a painting in 1904 and the sound poems were begun before DADA, and so on." -- Source of annotation: Marvin or Ruth Sackner.