Book  (Oct 2001)  Page(s) 140.  Includes photo(s).
 
Clematis 'Burford Variety'
Tangutica Group
(C. tangutica 'Burford Variety')
Found in John Treasure's garden (England) c. 1970
Introduced by Treasures of Tenbury c. 1970
Parentage believed to be C. tangutica x C. tibetana subsp. vernayi
... single, nodding, yellow flowers... four broad, pointed tepals... which remain almost closed, giving the flower a very rounded effect. Chocolate-brown stamens...