Book  (Jan 2000)  Page(s) 232.  
 
Shiuden Tree Peony. ex Japan [no date given]... purple

Article (website)  (1998)  Page(s) 4.  
 
In the year 1955, Egawa Kazei from Niigata City created new varieties like 'Echi no Akana', 'Shiunden' and 'Eikan', and Higuchi Yugen from Gosen City crossed a peony with a peony, from which emerged in 1962 the first yellow peony.

Website/Catalog  (1995)  Page(s) 55.  Includes photo(s).
 
SHIUNDEN : fleur double violet pourpré.