Book  (Apr 1993)  Page(s) 618.  
 
Ulster Gem Hybrid Tea, canary-yellow, single, 1917, Dickson, H. Description.

Book  (1936)  Page(s) 718.  
 
Ulster Gem (HT) H. Dickson 1917; canary-yellow, large, single, open, lasting, cluster-flowered, fragrance 3/10, mediocre, floriferous, continuous bloom, large leathery dark green foliage, growth 6/10, bushy.

Book  (1934)  Page(s) 81.  
 
A. D. Haff. Irish Singles. 'Ulster Gem' is another yellow of a lighter shade, less distinctive than 'Cecil' and less vigorous.

Book  (1934)  
 
Ulster Gem (H.T.): A single Rose, its large shell petals of deep primrose-yellow and its prominent and abundant anthers showing conspicuously on the large open flowers, frequently 6 inches in diameter, and of beautiful outline. Growth free and vigorous, producing its flowers in endless profusion throughout the season. Bed.

Website/Catalog  (1932)  Page(s) 29.  
 
'Ulster Gem'. HT. (H. Dickson, 1916). Large, canary-yellow flowers with slight fragrance, freely borne in clusters by a vigorous, well-branched plant. Large and very beautiful. 5 petals.

Book  (1932)  
 
H. R. Darlington. The Gold Medal Roses. 1883-1918.
....and 'Ulster Gem' (a single yellow) is now but little seen.

Website/Catalog  (1929)  Page(s) 34.  
 
Single Roses
These are Hybrid Tea Roses with single or almost single flowers, and require the same culture and care as the other Hybrid Teas. They are often called the "Irish Singles", although they are not all of Irish origin. The buds are especially fine, but the open flowers are rather perishable although they are very freely produced.
Ulster Gem. Hybrid Tea. (H. Dickson, 1916.) Large, canary-yellow flowers with slight fragrance, freely borne in clusters by a vigorous, well-branched plant. Large and very beautifully pointed buds for cutting.

Website/Catalog  (1923)  Page(s) 41.  
 
Hybrid Tea Roses .... Ulster Gem (H. Dickson, 1916). Single-blooming yellow passing to white. Fragrant. Gold Medal N.R.S.

Website/Catalog  (1922)  Page(s) 41.  
 
Single Flowering Roses.
Hybrid Teas.
Ulster Gem, deep primrose yellow, prominent anthers, flowers in profusion. Gold Medal, N.R.S. Free habit of growth.

Website/Catalog  (1922)  Page(s) 32.  
 
'Ulster Gem' (HT). A fine new single; pale primrose yellow.