Azalea rigida Rhododendron racemosum var. rigidum Rhododendron rarosquameum Rhododendron sycnanthum Rhododendron hesperium Rhododendron eriandrum Rhododendron bodinieri Rhododendron caeruleum
World Flora Online, http://www.worldfloraonline.org/, accessed June 20, 2024