Book  (Oct 2001)  Page(s) 140.  Includes photo(s).
 
Clematis 'Burford Bell'
Texensis-Viorna Group
(C. pitcheri 'Burford Bell')
John Treasure (England)
Named in 1991
Seedling of C. pitcheri
... single, small, nodding, greenish purple-blue bell-shaped flowers... four thick tepals... The insides of the tepals are purple...