Book  (Jan 2000)  Page(s) 231.  
 
Rimpou Tree Peony. ex Japan pre-1926... purple

Article (magazine)  (Jan 1955)  Page(s) 20.  
 
In purple, (Class VI), 'Rimpo' and 'Ruriban.'

Article (magazine)  (Jan 1955)  Page(s) 59.  
 
Alphabetical Check List of Tree Peony Names In  Public Collections And/or Available in Nurseries 1954-1955
Japanese, Purpla, 'Rimpo' (Bird of Rimpo) (Jap. bef. 1926), [Gardens] Scott Foundation, University of Washington Arboretum, Whitnal Park Botanical Gardens, [Nurseries] William Gratwick, Oberlin Peony Gardens

Website/Catalog  (1939)  Page(s) [1].  
 
Tree Peonies (Pæonia arborea)
Japanese Tree Peonies 
English translation in parentheses
53. Rimpo (Bird of Rimpow). Large, medium-double flowers of a reddish brown color... $10.00