Article (magazine)  (Jan 1955)  Page(s) 13.  
 
There were also hundreds of lilac pinks, magenta. pinks and plain magentas, most of which were very unattractive. Many closely resembled Banksi. Typical varieties were 'Archduc Ludovico,' 'Athlete,' 'Beaute de Twickel,' 'Jules PirIot,' 'La Ville de St. Denis,' 'Morris,' 'Princess Louise,' 'Reine Amelie,' 'Reine des Fleurs,' 'Triomphe de Vandermaelen,' and 'van Houttei.' All these varieties proved, in Holland and France, easy to propagate in comparison with the later introduced Japanese varieties. Which varieties bearing European names were actually raised from seed in Europe and which were Chinese varieties renamed is not too definitely established.

Article (magazine)  (Jan 1955)  Page(s) 56.  
 
Alphabetical Check List of Tree Peony Names In  Public Collections And/or Available in Nurseries 1954-1955
Chinese, Lilac Rose, 'Archduc Ludovico', (Bur. bef. 1867), [Nurseries] Cottage Gardens, Tingle Nursery Company

Book  (1928)  Page(s) 248.  
 
Tree Peony Check List
Archiduc Ludovico. Double. (Burdin, 1867.) A. Dessert 1889; V. Lemoine 1887; E. H. Krelage 1867; Louis Van Houtte 1873; Louis Paillet 1889.

Website/Catalog  (1921)  Page(s) 68.  
 
Paeonia arborea...Archiduc Ludovico. Large, fully double, light pink passing to soft lilac...1 piece M 15,00-25,00

Website/Catalog  (1903)  Page(s) 26.  
 
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...
Archiduco Ludovico. Double, clear rose-lilac.

Website/Catalog  (1890)  Page(s) 32.  
 
Pæonia Arborea (Tree or Moutan Pæonies).
General Collection.
Archiduc Ludovico, double, clear rosy lilac.

Magazine  (Jan 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:
Archiduc Ludovic...

Website/Catalog  (1876)  Page(s) 79.  
 
Paeonia arborea. Baumartige Paeonie.
Arciduca Ludovico, voll, weisslichrosa mit carmin, schön...2 50 M.

Website/Catalog  (1868)  Page(s) 25.  
 
Paeonia arborea.
68 Archiduc Ludovico, voll, hell rosalilla...20 Sgr.

Website/Catalog  (1866)  Page(s) 58.  
 
Pæonia Arborea. (Pivoines en arbres.)
Livrables en belles plantes.
Archiduc Ludovicoa...3 fr.