Compositae Working Group (CWG) (2024). Global Compositae Database.
Helianthus praecox subsp. runyonii (Heiser) Heiser. Accessed through: Marine Species Traits editorial board (2024) Marine Species Traits at: https://www.marinespecies.org/traits./aphia.php?p=taxdetails&id=1152065 on 2025-04-04
Marine Species Traits editorial board (2025). Marine Species Traits.
Helianthus praecox subsp. runyonii (Heiser) Heiser. Accessed at: https://www.marinespecies.org/traits/aphia.php?p=taxdetails&id=1152065 on 2025-04-04