Literature references

5 literature references:

Author: F.J. Chittenden
Year: 1951
Title:
Source: The RHS Dictionary of Gardening II. Oxford Univ.Press
Author: C. Stace
Year: 1991
Title:
Source: New Flora of the British Isles.Cambridge Univ.Press
Author: O. Polunin
Year: 1969
Title:
Source: Flowers of Europe. O.U.P.
Author: S. Ross-Craig
Year: 1954
Title:
Source: Drawings of British Plants Part VII.Reprinted 1979,Vol 3.
Author: H.J. Scoggan
Year: 1978
Title:
Source: Fl.Canada Part 3.National Museums of Canada, Ottawa