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, 'Regina Belgica' (Jap. Sieb.-K. or Mak. bef. 1867), [Nurseries] Oberlin Peony Gardens

Website/Catalog  (1924)  Page(s) 152.  
 
Pivoines en arbre...Reginæ Belgica.- Moyenne, neau rose tendre saumoné.

Website/Catalog  (1906)  Page(s) 37.  
 
Paeonia arborea. Tree-Peonies. A selection of especially fine double sorts.
Regina Belgica, salmon-pink, base flesh-coloured, loose fantasy-form with feathery bonnet

Website/Catalog  (1893)  Page(s) 42.  
 
Tree Pæonies.  Pæonia Arborea.
This beautiful group of shrubs is among the oldest of introductions from Japan, but magnificent new varieties have been added from year to year until we have a long list of wonderful forms.  They are quite distinct from the herbaceous section, and have shades of color not found in the latter; and when once established form compact bushes, which in spring are covered with the gigantic blooms.  These pæonies are a little tender in exposed situations north of Boston; but if planted in a sheltered, warm location, and protected during the first two winters by a covering of pine boughs, or other loose material, will eventually establish themselves, and form one of the most decorative features of the garden.  Like the herbaceous kinds, they enjoy rich soil, and the blooms last longer and come finer when partially sheltered from the hot sun.  They are well worth the little trouble entailed in their cultivation.  We can offer strong plants of the leading and most hardy kinds; but as they are slow and difficult of propagation, this fact will account for their relatively higher cost over the herbaceous kinds.  Having secured a large stock of these beautiful plants, we are enabled to offer them at lower prices than ever before.  2 year plants, 75 cents each; 3 year plants, $1.00 each.
Regina Belgica.  Large globular flower, salmon rose.  Extra.

Book  (1853)  Page(s) 1318.  
 
Nous citerons parmi les nouveautés:
...Athlète, Comte de Rambuteau, Eliarsii, Elisabetta, la Ville de Saint-Denis, Lambertina, Regina Belgica, Triomphe de Malines, Triomphe de Vandermalen et rubanée de Flandres.

Magazine  (1 Dec 1852)  Page(s) 200.  
 
Lambertinæ et Regina Belgica, ont été obtenus par M. Makoy de Liége. On trouve toutes ces nouveautés en france, mais en jeunes multiplications: nous n'en connaissons pas le mérite.