| APA | Smart Define. (-0001). two-tier thesaurus. Retrieved September 20, 2026, from https://smartdefine.org/two-tier/thesaurus/synonyms |
| Chicago | Smart Define. -0001. "two-tier thesaurus" https://smartdefine.org/two-tier/thesaurus/synonyms (accessed September 20, 2026). |
| Harvard | Smart Define -0001, two-tier thesaurus, Smart Define, viewed 20 September, 2026, <https://smartdefine.org/two-tier/thesaurus/synonyms>. |
| MLA | Smart Define. "two-tier thesaurus" 30 November -0001. Web. 20 September 2026. <https://smartdefine.org/two-tier/thesaurus/synonyms> |