Verbatim text: Bierner, M. W. 1989. Taxonomy of Helenium sect. Amarum (Asteraceae). Sida 13: 453–459.
Author: Bierner, M.W.
Year: 1989
Title: Taxonomy of Helenium sect. Amarum (Asteraceae)
Journal: Sida
Volume: 13
Pages: 453–459