Article (magazine)  (Jan 1955)  Page(s) 59.  
 
Alphabetical Check List of Tree Peony Names In  Public Collections And/or Available in Nurseries 1954-1955
Chinese, Rose Red, 'Purity' (Named Pai. 1889), [Gardens] Whitnal Park Botanical Gardens

Website/Catalog  (1920)  Page(s) 6.  
 
List of Varieties...
Purity, flesh, slightly shaded carmine...

Website/Catalog  (1885)  Page(s) 72.  
 
Pivoines en Arbres.
Variétés de 1^er ordre disponibles en bonnes plantes.
85 Purity (Berger)...2 fr.
Blanc très pur.