Verbatim text: Ockendon, D. L., S. M. Walters, and T. P. Whiffen. 1969. Variation within Centaurea nigra. Proc. Bot. Soc. Brit. Isles 7: 549–552.
Author: Ockendon, D.L., Walters, S.M., Whiffen, T.P.
Year: 1969
Title: Variation within Centaurea nigra
Journal: Proc. Bot. Soc. Brit. Isles
Volume: 7
Pages: 549–552