Canadensys: University of Alberta Vascular Plant Herbarium (ALTA-VP)
Canadensys, operated from the Université de Montréal Biodiversity Centre
"113133 - Penstemon procerus Douglas ex Graham, University of Alberta Vascular Plant Herbarium." University of Alberta Museums Search Site, https://search.museums.ualberta.ca/12-19459. Accessed 15 Jan. 2025.