Book  (1941)  Page(s) 113.  
 
Georges Bugnet.  The Search for Total Hardiness
...Frau Dr. Erreth, a thornless double yellow polyantha

Book  (1936)  Page(s) 241.  
 
Erreth, Frau Dr. (Pol) Geduldig 1915; Gruss an Aachen X M. A. Ward; yellowish orange to golden-yellow; fades to whitish, large, double, solitary or up to 5, floriferous, growth 5/10, well-branched. Sangerhausen

Website/Catalog  (1931)  Page(s) 32.  
 
Larger bloomed Polyantha Roses ....Frau Dr. Erreth yellow Gruss an Aachen... 0,70 Marks [10] 6,30 [100] 56,--

Magazine  (1931)  Page(s) 303.  
 
...medium tall sorts are for example: 'Erna Teschendorff', 'Frau Dr. Erreth', 'Echo', 'Locarno', 'Gruss an Aachen', 'Jessy', 'Katharina Zeimet', 'Präsident Hindenburg'....

Website/Catalog  (1929)  Page(s) 43.  
 
Polyantha Roses
Polyanthas are, perhaps the most truly everblooming of all Roses, being scarcely ever out of flower during the whole growing season... They are especially valuable for massing, edging, and to some extent for mingling with other flowers.
Frau Dr. Erreth. (Geduldig, 1915.) Flowers very large for a Polyantha, deep golden yellow, becoming white with age, very double, well-shaped, and borne in sparse clusters. Moderate, branching growth; healthy and hardy.
Resembles a small Mrs. Aaron Ward. A most promising bedding and buttonhole variety. We are still waiting for a good, golden yellow variety. If Frau Dr. Erreth were more vigorous, it would fill the requirements. It is somewhat like Gruss an Aachen in type but not as free-flowering.

Book  (1926)  
 
p53. There are several well-defined types in this [polyantha] class, including a comparatively large-flowered group which is quite attractive. Of these, 'Gruss an Aachen' and possibly Frau Dr. Erreth are fairly good as roses, and beds of them would be acceptable among the Hybrid Teas. The fact is that the only reason those varieties are acceptable for that purpose is because they diverge so far from the true Polyantha type that they are almost Hybrid Teas.

p55. Frau Dr. Erreth (Geduldig, 1915): deep-orange double blooms, much resembling 'Mrs. Aaron Ward' and, like it, fading to white when fully open. Very large and attractive for a Polyantha.

Website/Catalog  (1925)  Page(s) 84.  
 
Rosa Polyantha...Frau Dr. Ereth. Counterpart to the popular large-bloomed Polyantha rose Gruss an Aachen. Golden-yellow, light yellow when fading. ...Low-grafted garden plants 1 piece G.-M. [Gold-Mark] 1.50

[no longer listed in the 1929 catalogue]