Abstract: Apparatus for singulating respective documents fed thereto, wherein each of the documents is uprightly oriented on an edge thereof and has oppositely facing upright surfaces, and wherein each successive document is slidably movable relative to a next successive document against an interdocument frictional force developed therebetween, the apparatus comprising: first document feeding structure including two first belts, the first feeding structure including first structure for moving the first belts downstream relative to a path of travel in vertically spaced first belt runs; second document feeding structure including a second belt, the second feeding structure including second structure for moving the second belt upstream relative to the path of travel in a second belt run, the second feeding structure including structure for resiliently urging the second belt run into interleaving relationship with the first belt runs; and the first belt runs exerting a downstream frictional force greater than the interdocu