Rhododendron sanguineum var. haemaleum Rhododendron sanguineum var. didymoides Rhododendron sanguineum var. sanguineum Rhododendron sanguineum var. himertum Rhododendron sanguineum var. cloiophorum Rhododendron sanguineum var. didymum
World Flora Online, http://www.worldfloraonline.org/, accessed June 20, 2024