Book  (1936)  Page(s) 649.  
 
Schmetterling (hybrid lutea) Dr. Müller 1905; yellow and red mixed, medium-size, semi-double, flat, solitary or up to 7, fragrance 4/10, slight repeat, growth 7/10, upright, 1,50 m., hardy. = Sultan. Sangerhausen

Book  (1936)  Page(s) 686.  
 
Sultan = Schmetterling. Sangerhausen