Article (magazine)  (2011)  Page(s) 118.  
 
Questionable rose identities: We do not recognize following rose cultivars of Rudolf Geschwind as corresponding to the historical descriptions:....'Erlkönig' - Multiflora, 1886....

Book  (2003)  Page(s) 57-58.  
 
Geschwind's Hybrids of 'De La Grifferaie'....
'Erlkönig' syn. 'Roi des Aunes' (Geschwind, 1885).

Book  (Apr 1993)  Page(s) 500.  
 
Roi des Aunes Shrub, carmine tinted red, 1885, ('Erlkönig'); Perhaps raised from 'De la Grifferaie'; Geschwind. Description.

Book  (1980)  Page(s) 62.  
 
(from: Möller’s Deutsche Gärtner-Zeitung 1886, p. 66-67)
…Rud. Geschwind sent us last autumn 13 different climbers under the name „Hungarian Climbers“ to bring into commerce and thus have them tested by roselovers…
Erlkönig: Strong sort of Multiflora de la Grifferaie, with rough, thorny, strong canes, which mostly stand out horizontal and arch. Dark green foliage, almost evergreen, beautiful. Blooms in clusters. Medium size blooms, flat cup form, well double and fine form, light carmine-purple, often passing to crimson. Effectful and hardy!

Book  (1954)  Page(s) 36.  
 
Another somewhat distinct and extremely hardy group is known as the Hungarian Roses. They are mostly hybrids of R. multiflora with R. rugosa annd other hardy roses, and are credited to Geschwind of Karpona, Hungary. Representative varities are Château Luegg, Décoration de Geschwind, Gilda, Roi des Aunes, and Schneelicht.

Book  (1936)  Page(s) 241.  
 
Erlkönig (Multiflora) Geschwind 1886; de la Grifferaie X ?; light carmine-purple to crimson, medium-size, double, fine form, cupped, cluster-flowered, growth 8/10, climbing

Book  (1933)  Page(s) 210.  
 
ROI DES AUNES. Geschwindt, 1885. Classed as a Multiflora. Reputed to have large, globular, bright red flowers.

Magazine  (Jun 1929)  Page(s) 72.  
 
Roi des Aulnes (Geschwind!, 1885), fleur grande, pleine, bombée, carmin nuancé de rose vif.

Website/Catalog  (1914)  Page(s) 4.  
 
Once-blooming climbers. Erlkönig, light carmine-purple, medium size, double

Book  (1912)  Page(s) 128.  
 
Roi des Aunes, Geschwindt 1885, Carmin nuancé de rouge vif.- fl. grande, pleine, bombée; assez vigoureuse.