Book  (2007)  
 
'Postjärnan' Polestar, The Polar Star, The Wasa Star, Wasastiernan, White Rose of Finland, White Star of Finland
LCl, w, 1937, Wasastjerna. Includes description.

Magazine  (1998)  Page(s) 109. Vol 92, Part 4.  
 
Dr. Alan S. Harris. Northern Lights and Nordic Roses.
'Polstjarnan' is a hybrid of R. beggeriana and was introduced by Wasastjarna in Finland in 1937......