Verbatim text: Panjabi, S. S. and D. G. Anderson. 2006. Penstemon harringtonii Penland (Harrington’s Beardtongue): A Technical Conservation Assessment. Fort Collins.
Author: Panjabi, S.S., Anderson, D.G.
Year: 2006
Title: Penstemon harringtonii Penland (Harrington’s Beardtongue): A Technical Conservation Assessment