López, E.; Devesa, J. A. Taxonomic Notes on Genus Centaurea L. (Asteraceae) in the Iberian Peninsula. I. C. Cordubensis Font Quer, C. Bethurica E. López & Devesa, Sp. Nov., and C. Schousboei Lange. An. Jard. Bot. Madr. 2008, 65, 331-341.