File:Vintage Casio-Mini Electronic Pocket Calculator, Made In Japan, Green Fluorescent Display, Circa 1972 (15804894498).jpg - Wikimedia Commons
File:Vintage Casio-Mini Electronic Pocket Calculator, Model CM-602, 6 Digit Fluorescent Display, Made In Japan, Circa 1973 (28964447948).jpg - Wikimedia Commons
Casio Personal Mini Handheld Electronic Calculator | National Museum of American History