Literature
- Stace, C. ( 1997. ) New Flora of the British Isles. Cambridge University Press, The Bath Press, UK.
- Tutin, T. G., V. H. Heywood, N. A. Burges, D. M. Moore, D. H. Valentine, S. M. Walters and D. A. Webb (eds.) ( 1980. ) Flora Europaea, Volume 5. Cambridge University Press, Cambridge, UK.
- Webb, D. A. and M. J. P. Scannell ( 1983. ) Flora of Connemara and the Burren. Royal Dublin Society and Cambridge University Press, Cambridge, UK.
- Webb, D. A., J. Parnell and D. Doogue ( 1996. ) An Irish Flora. Dundalgan Press, Dundalk.