Canadensys: University of Alberta Vascular Plant Herbarium (ALTA-VP)
Canadensys, operated from the Université de Montréal Biodiversity Centre
"23072 - Betula papyrifera Marshall var. commutata (Regel) Fernald, University of Alberta Vascular Plant Herbarium." University of Alberta Museums Search Site, https://search.museums.ualberta.ca/12-101801. Accessed 26 Apr. 2025.