Verbatim text: Moore, R. J. 1972. Distribution of native and introduced knapweeds (Centaurea) in Canada and the United States. Rhodora 74: 331–346.
Author: Moore, R.J.
Year: 1972
Title: Distribution of native and introduced knapweeds (Centaurea) in Canada and the United States
Journal: Rhodora
Volume: 74
Pages: 331–346