Hernández-Barón, Gerald Matus, Diana Isabel Trujillo Juárez, and Victor W. Steinmann. 2023. “Polystemma stevensii (Apocynaceae, Asclepiadoideae), a New Species from Michoacán, Mexico”. Phytotaxa 613 (2). Auckland, New Zealand:194-200. https://doi.org/10.11646/phytotaxa.613.2.9.