Answer
Centaurea is a genus of plants that includes many species, including the cornflower and knapweed. August von Hayek was an Austrian botanist who worked with Centaurea and other plants. He published several books on the genus, including "Centaurea: Monographie der Gattung" (1926) and "Centaurea: Supplementum" (1934). Hayek's work on Centaurea was significant for its detailed descriptions of the species and its classification of the genus.