Canadensys: University of Alberta Vascular Plant Herbarium (ALTA-VP)
Canadensys, operated from the Université de Montréal Biodiversity Centre
"9789 - Erysimum asperum (Nutt.) DC., University of Alberta Vascular Plant Herbarium." University of Alberta Museums Search Site, https://search.museums.ualberta.ca/12-120330. Accessed 11 Apr. 2025.