Booklet  (1938)  Page(s) 126.  
 
Japanese Peonies (albiflora)
Emperor of India* (45)
Large, bright amaranth purple, midseason. Staminodes purple-tinged on upper surface, with yellow filaments. Carpels sparsely hairy, tips bright red; disk conspicuous, pink. Plant medium size, compact; many attractive flowers showing high above the foliage.

Website/Catalog  (1935)  Page(s) 11.  
 
Kelway's "Imperial" Pæonies.
June-flowering.
Emperor of India. Rich dull purple petals, with a cushion of gold at the centre; large and handsome; late mid-season. Extra....30/-

Book  (1907)  Page(s) 115.  
 
1252. INDiA. EMPEROR OF; P.
(1) 1906, Kelway's Cat., p. 113.

Website/Catalog  (1903)  Page(s) 20.  
 
Kelway's New "Imperial" Peonies of 1902.
Emperor of India, very large flower, with two rows of very broad and deep petals of richest blue-madder colour; most striking. 7/- each.