Book  (2006)  Page(s) 76.  
 
Robert Duncan HP. Good, reliable rebloom. Outstanding fragrance. Stouter canes. Dickson, 1897. ..Immense cups of carmine pink with many petals and Damask perfume..

Book  (Apr 1993)  Page(s) 499.  
 
Robert Duncan Hybrid Perpetual, purplish pink, sometime flamed brilliant red, 1897, Dickson, A. Description.

Book  (1936)  Page(s) 224.  
 
Duncan, Robert (HP) A. ickson 1897; glossy lake-red to salmon-pink, large, double, flat, fine form, broad petals, floriferous, autumn-bloomer, growth 6/10, upright. Sangerhausen

Website/Catalog  (1924)  Page(s) 30.  
 
Robert Duncan. — Rose laqué luisant. Variété de grand mérite, vigoureuse.

Website/Catalog  (1914)  Page(s) 13.  
 
Hybrid Perpetual Roses.
Robert Duncan, Alex. Dickson & Sons, Ltd., 1897, vigorous. Bright rosy-lake; very floriferous; fragrant.

Website/Catalog  (1913)  Page(s) 26.  Includes photo(s).
 
Hybrid Perpetual Roses.
Robert Duncan is a generous-flowering, fragrant Rose, the blossoms of which are large, perfectly formed and graceful in their proportions. The petals are large, shell-shaped and curly. The plant obtains moderate size, but is of sturdy formation. The color- light scarlet or rosy lake- is delicate from the first faint streaks observable, as the buds begin to open, until the petals fall. When planted in masses the effect is decidedly pleasing.

Magazine  (5 Aug 1911)  Page(s) 374.  
 
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...
Robert Duncan... Hybrid Perpetual, A. Dickson, 1897, Charles Lefebvre race

Website/Catalog  (1911)  Page(s) 25.  
 
Hybrid Perpetual Roses. Robt. Duncan. A fine exhibition flower, of a deep rosy lake.

Book  (1910)  Page(s) 294.  
 
Robert Duncan Hybrid Perpetual: flowers bright rosy lake, large and of good form.

Booklet  (1904)  Page(s) 23.  
 
Robert Duncan.....A good show variety.  Vig. Exh. Gdn.