Radical 14, meaning cover, is one of 23 of the 214 Kangxi radicals that are composed of 2 strokes. In the Kangxi Dictionary there are 30 characters (out of 40,000) to be found under this radical.
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