Verbatim text: Every, A. D. 1977. Biosystematics of Penstemon Subgenus Dasanthera—A Naturally Hybridizing Species Complex. Ph.D. dissertation. University of Washington.
Author: Every, A.D.
Year: 1977
Title: Biosystematics of Penstemon Subgenus Dasanthera—A Naturally Hybridizing Species Complex