Attributes / relations provided by
♦ 1ECOFACT 2a Technical Annex - Ellenberg’s indicator values for British Plants, M O Hill, J O Mountford, D B Roy & R G H Bunce (1999)
♦ 2PLANTATT - Attributes of British and Irish Plants: Status, Size, Life History, Geography and Habitats, M. O. Hill, C. D. Preston & D. B. Roy, Biological Records Centre, NERC Centre for Ecology and Hydrology (2004)
♦ 3Robertson, C.
Flowers and insects lists of visitors of four hundred and fifty three flowers. 1929. The Science Press Printing Company Lancaster, PA.