Book  (1936)  Page(s) 320.  
 
Grümmer, Franz (HT) Maass 1927; M. A. Chatenay X Ch. Cl. Vougeot; bright coral-pink to vivid red, very large, well double, lasting, solitary, fragrance 3/10, floriferous, growth 7/10, lanky. Sangerhausen

Book  (1936)  Page(s) 112.  
 
Brümmer, Franz (HT) Maass 1927; M. A. Chatenay X Ch. Cl. Vougeot; bright coral-pink, large, double, lasting, open, fragrance 3/10, floriferous, long upright stems, growth 6/10.

Magazine  (1932)  Page(s) 20.  
 
I found 6 German rose nurseries represented with novelties: Conrad Maaß with the roses Marie Maaß, Conrad Maaß and Franz Grümmer.