The only left-falling stroke in Radical 4, known as 撇piě, is basic to Chinese calligraphy. It has two different forms, 掠 lüè and zhuó, in the eight principles of 永 (永字八法Yǒngzì Bāfǎ).
Literature
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 (1993). Tracing the Roots of Chinese Characters: 500 Cases. Beijing. ISBN978-7-5619-0204-2.{{cite book}}: CS1 maint: location missing publisher (link)
External links
Wikimedia Commons has media related to Radical 004.
GF 0011-2009 Table of Indexing Chinese Character Components prescribes 201 principle indexing components and 100 associated indexing components (in brackets) used in Simplified Chinese. Not all associated indexing components are listed above.