1. There’s plenty of room at the bottom;Feynmann;Eng Sci,1960
2. www.youtube.com: Feynman: Take the world from another point of view (1/4).
3. Nanomaterials history, classification, unique properties, production and market;Sudha,2018
4. The implications and applications of nanotechnology in dentistry: a review;AlKahtani;Saudi Dent J,2018
5. A brief history of LED photopolymerization;Jandt;Dent Mater,2013