See handwriter in action on handwriting examples from the CSAFE Handwriting Database.
The demo treats CSAFE writers "w0009", "w0030", "w0203", "w0238", and "w0400" as example Persons of Interest (POIs). Three repetitions of the Wizard of Oz prompt from each POI serve as the known writing samples.
A London Letter prompt from writers "w009", "w0030", and "w0238" serve as example questioned documents.