In 1933, artist and color researcher Sanzo Wada published 配色総鑑 (Haishoku Soukan), a comprehensive guide to color harmony from the Taisho and early Showa eras. Seigensha later reissued this work in English as A Dictionary of Color Combinations in 2010. This site is a digital reference for all 348 combinations, with every color converted to digital color values.