| APA | Smart Define. (2011). rare-earth element thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/rare-earth_element/thesaurus/narrower |
| Chicago | Smart Define. 2011. "rare-earth element thesaurus" https://smartdefine.org/rare-earth_element/thesaurus/narrower (accessed September 24, 2026). |
| Harvard | Smart Define 2011, rare-earth element thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/rare-earth_element/thesaurus/narrower>. |
| MLA | Smart Define. "rare-earth element thesaurus" 23 May 2011. Web. 24 September 2026. <https://smartdefine.org/rare-earth_element/thesaurus/narrower> |