A finger-operated page turning device for stacked sheets, with methods, apparatus for forming the device as sets offset voids or notches in alternating pages of a stack. The first and second reference layers are antiferromagnetically coupled. These surfaces cannot be disinfected with conventional alcoholic disinfectants. A heater control circuit is provided for causing the band heater to be normally energized for a preassigned period of time at regular intervals during the operation of the apparatus, keeping the heater heated to a temperature necessary for melting the thermoplastic overlay of the paper band. A color display may be generated from a single display element by modulating the pitch length of the cholesteric material. The card game can be played in a physical environment as well as a digital environment.