| APA | Smart Define. (2011). research project thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/research_project/thesaurus/narrower |
| Chicago | Smart Define. 2011. "research project thesaurus" https://smartdefine.org/research_project/thesaurus/narrower (accessed September 21, 2026). |
| Harvard | Smart Define 2011, research project thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/research_project/thesaurus/narrower>. |
| MLA | Smart Define. "research project thesaurus" 26 April 2011. Web. 21 September 2026. <https://smartdefine.org/research_project/thesaurus/narrower> |