Canadensys: University of Alberta Vascular Plant Herbarium (ALTA-VP)
Canadensys, operated from the Université de Montréal Biodiversity Centre
"135519 - Helianthus pauciflorus Nutt. ssp. subrhomboideus (Rydb.) O. Spring & E. E. Schill., University of Alberta Vascular Plant Herbarium." University of Alberta Museums Search Site, https://search.museums.ualberta.ca/12-140225. Accessed 26 Apr. 2025.