Verbatim text: Weber, W. A. 1952. The genus Helianthella (Compositae). Amer. Midl. Naturalist 48: 1–35.
Author: Weber, W.A.
Year: 1952
Title: The genus Helianthella (Compositae)
Journal: Amer. Midl. Naturalist
Volume: 48
Pages: 1–35
PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/2422128