Sandwich keyboard: fast ten-finger typing on a mobile device with adaptive touch sensing on the back side. - Oliver Schoenleben; Antti Oulasvirta (Mobile HCI, 2013)

Improving accuracy in back-of-device multitouch typing: a clustering-based approach to keyboard updating. - Daniel Buschek; Oliver Schoenleben; Antti Oulasvirta (IUI, 2014)