Ranunculus - Buttercup

I had this lovely example from the Slavonian Grebe lake down as a common Buttercup or Ranunculus sp. Having checked the Collins Wildlife book, I can't find one with just the very small white edging to the flower petals. will have to check it out further and enter a more precise name as and when found.
Ref:
Date:
14/06/10
Location:
Aigas Field Centre
Photographer:
John Pell