Sheffield, Cory S. “A Review of the Stelidium Group of Stelis Panzer, 1806 (Hymenoptera: Megachilidae) With Two New Species from Western North America”. Zootaxa 5404, no. 1 (January 25, 2024): 134–166. Accessed April 3, 2025. https://mapress.com/zt/article/view/zootaxa.5404.1.10.