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.