1. Harvard Design School Guide to Shopping. Harvard University Graduate School of Design
2. DNP Holo Screen holographic rear projection screen,
http://www.en.dnp.dk/
3. Pronova HoloPro screen,
http://www.gb-pronova.de/en/index/
4. 3M MicroTouchTM ClearTekTM II Capacitive Touch Screens,
http://solutions.3m.co.uk/wps/portal/3M/en_GB/TouchScreens/
5. NextWindow optical touch screen technology,
http://www.nextwindow.com/benefits/touchscreen_technology.html