Book  (Apr 1993)  Page(s) 44.  
 
Belle Blanca Large-flowered Climber, Probably a 'Belle Portugaise' white sport; After 1903.

Book  (Jun 1992)  Page(s) 205.  
 
Belle Blanca. Introducer and date unknown. Hybrid Gigantea. Presumably a sport of 'Belle Portugaise'. Description.

Website/Catalog  (1947)  Page(s) 1.  
 
Belle Blanca. Same as above [Belle of Portugal] Same as above except satiny white.