Radical 7 or radical two (二部) meaning "two" is one of 23 of the 214 Kangxi radicals that are composed of 2 strokes.
In the Kangxi Dictionary, there are 29 characters (out of 49,030) to be found under this radical.
In Simplified Chinese dictionaries and some Hong Kong Traditional Chinese dictionaries, radical 7 (radical two) is merged with radical 1 (Radical one, 一).
Fazzioli, Edoardo (1987). 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, ISBN978-7-5619-0204-2