4 literature references:

Author: Stace,C.
Year: 1991
Title:
Source: New Flora of the British Isles.Cambridge Univ.Press
Author: Harden,G.J.(Ed.)
Year: 1991
Title:
Source: Flora of New South Wales,Vol 2. Kensington: New South Wales
Author: Terrell,E.E.
Year: 1977
Title:
Source: Checklist of Names for 3,000 Vas.Pl... Agric.Handbook No.505
Author: Townsend, C.C. & Guest, E.
Year: 1974
Title:
Source: Flora of Iraq. Vol.3. Baghdad.