Website/Catalog  (2020)  Page(s) 211.  Includes photo(s).
 
Si, Pere Dot, 1957, miniature, microminiature, light pink, very small, approx. 5 mm, Perla de Montserrat X (Anny X Tom Thumb), very small growth, bibliography: LD - mcf10

Book  (10 Sep 2009)  Page(s) 167.  
 
Si, Miniature. Introduced: Dot, Spain, 1957.  The smallest rose in the world, and worth growing for its novelty value. 'Si' has white buds, shaded pale pink in cool weather, no larger than a kernel of wheat. The buds are much more charming than the insubstantial white flowers that follow. The plant reaches about 8" for me and offers repeat bloom very quickly. You'd need to use manicure scissors to deadhead it, but I have never found this to be necessary as the plant is apparently sterile and puts no effort into setting seeds.

Book  (1996)  Page(s) 125.  Includes photo(s).
 
Si Miniature bush. Sean McCann considers this the smallest of the miniatures... Dot 1957

Book  (Apr 1993)  Page(s) 549.  
 
Si Miniature, rosy white, micro-mini, 'Perla de Montserrat' x ('Anny' x 'Tom Thumb'); Dot, P. Description.

Book  (1991)  Page(s) 13.  
 
The smallest [miniature] in commerce is Si, with a bud that is not much bigger than a wheat grain.

Book  (1958)  Page(s) 376.  
 
Si. Min. (P. Dot, '57.) Perla de Montserrat X (Anny X Tom Thumb). Small, rosy white. Dwarf; abundant bloom. (14)

Magazine  (Sep 1957)  Page(s) 3. trimester, p. 17.  
 
PALMARES DU 2ème CONCOURS INTERNATIONAL DE ROSES NOUVELLES DE MADRID — 21 JUIN 1957 .... CERTIFICAT DE MÉRITE : Au rosier miniature blanc rosé « Si ». Obtenteur : M. P. Dot, Espagne.