Book  (Oct 2001)  Page(s) 107-108.  Includes photo(s).
 
Clematis 'Alborosea'
Atragene Group
(C. macropetala 'Alborosea')
[Raised by] Magnus Johnson (Sweden) from seed given to him by Hans R. Horngfeller of Merligen, Switzerland, 1974
Chance seedling of C. macropetala
... double, nodding, mauvish pink flowers... four narrow spear-shaped tepals, each boasting long veins of a darker shade running from the base to the tip... occasional midsummer flowers...