Verbatim text: Crosswhite, F. S. 1967c. Revision of Penstemon section Habroanthus (Scrophulariaceae) III: Series Virgati. Amer. Midl. Naturalist 77: 28–41.
Author: Crosswhite, F.S.
Year: 1967c
Title: Revision of Penstemon section Habroanthus (Scrophulariaceae) III: Series Virgati
Journal: Amer. Midl. Naturalist
Volume: 77
Pages: 28–41