Book  (2015)  Page(s) 171.  
 
The 1961 autumn edition of the Cazzaniga catalogue includes a listing of the following novelties.....These are followed by 'Letizia' ('Hawaii' x unnamed seedling)....

Website/Catalog  (2000)  Page(s) 118.  
 
Grandiflora. Letizia, Cazzaniga F.G., 1962