Article (misc)  (11 Dec 2010)  
 
Percy Wright Autobiography, Volume IV, Page 1008

For example, the rose Harison's Yellow kills to the snowline at Parkside every winter, whereas here at Saskatoon it is abundantly hardy. Prof. J. T. Maney's Ames 6 (Multiflora x Blanda) behaves similarly, and so does Prof. N.E. Hansen's Alika. So does my Eureka rose. The latter is a seedling of Ames 6 with semidouble white flowers instead of single pale-pink ones, that I raised about 1945 while at Moose Range.

Book  (Apr 1993)  Page(s) 166.  
 
Eureka Shrub. P.H. Wright 1956. Parentage probably 'Betty Bland' x 'Ames 5'... Flowers pure white... less vigorous than 'Ames 5'... intended for trial as a hardy understock

Book  (1967)  Page(s) 47.  
 
Some All-Canadian Roses
by Fred Blakeney, Victoria, B.C.
Mr. Percy Wright of Saskatoon, Sask., must be considered one of the foremost hybridizers of species and near species roses in North America. He has been working on these roses for many years, and knows the reactions of various hardy roses when crossed with species roses.
His objective has always been to produce worthwhile garden roses that are hardy enough to withstand the extremely low temperatures of the Prairies in winter. [...]
Here is a list of Mr. Wright's originations in chronological order of introduction:
1956 "Eureka", small, semi-double white flowers in clusters.