Fazzioli, Edoardo. Chinese calligraphy : from pictograph to ideogram : the history of 214 essential Chinese/Japanese characters. calligraphy by Rebecca Hon Ko. New York: Abbeville Press. ISBN0-89659-774-1.
Leyi Li: “Tracing the Roots of Chinese Characters: 500 Cases”. Beijing 1993, ISBN 978-7-5619-0204-2