An intuitive model of perceptual grouping for HCI design. - Ruth Rosenholtz; Nathaniel R. Twarog; Nadja Schinkel-Bielefeld; Martin Wattenberg (CHI, 2009)

Playing with Puffball: simple scale-invariant inflation for use in vision and graphics. - Nathaniel R. Twarog; Marshall F. Tappen; Edward H. Adelson (SAP, 2012)