Article (website)  (2016)  
 
Karl Feodorovich had four children: Sofia (1852), Amalia (1853), Wilhelm (1855) and Katharina (1857). The latest, after studying at Dorpat (1871-1874), became a pharmacist in the chemist’s shop of the Imperial Court, and in December, 1880, married Leonhard Gerhen. The famous Luxembourg rosarian Jean Ketten called his new tea rose in honor of Katharina Freundlich–‘Catherine Gerchen-Freundlich’ (T,Ketten,1896).

Book  (1936)  Page(s) 295.  
 
Gerchen-Freundlich, Catherine (tea) Ketten 1897; Alph. Karr X L. Zoé Brougham; pink, marbled coppery red, edges crimson, large, double, growth 6/10.

Magazine  (20 May 1911)  Page(s) 243.  
 
The Parentage of Roses.
The following list of the world's Roses and their parentage has been compiled by Mr. Robert Daniel, 38 Russell Road. Fishponds, Bristol, and by his kind permission we are enabled to publish it...
Catherine Gerchen-Freundlich... Tea, Ketten, 1896, Alphonse Karr X Lady Zoë Brougham

Book  (1902)  Page(s) 69.  
 
Thé. 1336. Catharina Gerchen Freundlich (Ketten 1896), carmin et cuivré.

Book  (1899)  Page(s) 33.  
 
Catharina Gerchen Freundlich, thé, Ketten, 1896, carmin et cuivré