Article (magazine)  (Jan 1955)  Page(s) 57.  
 
Alphabetical Check List of Tree Peony Names In  Public Collections And/or Available in Nurseries 1954-1955
Japanese, Lilac Rose, 'Imperatrice Josephine' (Hiss 1939), [Gardens] Whitnal Park Botanical Gardens

Website/Catalog  (1903)  Page(s) 27.  
 
Pæonia Arborea (Tree Peonies)
The Tree Peony is really one of the finest plants available for the garden or the conservatory; it is quite hardy and does well under the simplest treatment. The smallest one will flourish in the most astonishing manner, bearing blossoms from 6 to 8 inches across, which will increase every year in beauty and size. In colors, the flowers range in great variety, from a white to a nearly reddish black. [...]
Price: Two-year old, named varieties, purchaser's selection, $1.25 each, $12.00 per dozen...
Imperatrice Josephine. Double, clear lilac, center carmine rose.

Book  (1898)  Page(s) 107.  
 
La Pivoine en arbre a fourni à la culture un grand nombre de variétés horticoles, les unes obtenues en Chine, et d'autres en Europe...Quant aux variétés horticoles, elles sont si nombreuses que nous ne pouvons citer que les plus remarquables.
Principales Variétés Horticoles
Impératrice Joséphine.—Beau rose vineux.

Magazine  (20 Apr 1889)  Page(s) 354.  
 
Moutan Paeonies in pots.—Although it is a century since the Moutan or Tree Pæony was introduced into this country, it is by no means a common plant, and is not grown nearly as much as its merits deserve.  Many of the new varieties far excel the typical form both in size and colour of the flowers.  Pæonies will not force early, but grown as pot plants and kept in a cold frame, they produce a grand display of bloom at this time of year.  Being gross feeders they require liberal treatment, and should never be allowed to get dry.  Amongst the best varieties are Reine Elizabeth, Comte de Flandres, Caroline, Impératrice Josephine, and Salmonea.  A fine group of these is a great attraction in the greenhouse at Kew. — F. G.

Magazine  (22 Jan 1887)  Page(s) 77.  
 
The Tree Pæony. 
...For the last twenty years or longer we have had to look to our French neighbours for new sorts of Tree Pæony, for since they have taken the work of hybridising and raising seedlings in hand they have supplied us with all the finest sorts.  Until now the list is long- too long, in fact, for names are given where very shadowy differences exist.
List of select Varieties.
Impératrice Josephine, rich rose, splashed with red

Website/Catalog  (1886)  Page(s) 103.  
 
Select Varieties of Pæonia Moutan.
P. Josephine Imperatrice. Dark rose, with a purple shade; distinct. $1.00.

Magazine  (Jun 1885)  Page(s) 203.  
 
Association Horticole Lyonnaise
Procès-verbal de la séance du 16 mai 1885, tenue dans la salle des réunions industrielles, Palais du commerce, à Lyon.
Examens des apports.—Sont déposés sur le bureau:
1º Par M. Pernet fils-Ducher, un lot remarquable de Pivoines fleuries (fleurs coupées), parmi lesquelles se faisait distinguer le superbe gain de cet érablissement: Souvenir de Ducher.
Les autres variétés de Pivoines en arbre étaient:
Impératrice Joséphine...

Website/Catalog  (1871)  Page(s) 26.  
 
Paeonia arborea.
—Impératrice Joséphine...5 L.

Website/Catalog  (1868)  Page(s) 26.  
 
Paeonia arborea.
10 Impératrice Joséphine, sehr gross, sehr voll, lebhaft rosalilla, Centrum monströs...10 Sgr.

Website/Catalog  (1865)  Page(s) 19.  
 
Pivoines en arbre. Pæonia arborea.
Impératrice Joséphine, fleur rouge violacé très grande...2 fr.