1. Lambert Johann H., Photometria sive de mensura de gratibus lumi-nis, colorum et umbrae, Augsberg, Germany: Eberhard Klett (1760). English translation from the Latin by Dilaura David L., Photometry, or, On the measure and gradations of light, colors, and shade. Illuminating Engineering Society of North America, p. 423 (2002) ISBN 0879951796. [These two famous books were written in 1760. Many of the current ideas about radiometry and photometry can be traced to Bouguer and Lambert. Lambert is famous for Lambert's Law; he also developed a formula for the irradiance due to a polygonal source. Bouguer is famous for introducing the idea of estimating radiant intensity using the relative distance between a light source and a standard candle.]