Cistus hirsutus var. nigrescens Cistus hirsutus var. psilosepalus Cistus psilosepalus Cistus subhirsutus Cistus laxus var. trichocalyx Cistus laxus var. nigrescens Cistus laxus f. pedroi Cistus laxus var. subhirsutus Cistus nigrescens
World Flora Online, http://www.worldfloraonline.org/, accessed June 20, 2024