| APA | Smart Define. (2016). unbelievable thesaurus. Retrieved September 26, 2026, from https://smartdefine.org/unbelievable/thesaurus/narrower |
| Chicago | Smart Define. 2016. "unbelievable thesaurus" https://smartdefine.org/unbelievable/thesaurus/narrower (accessed September 26, 2026). |
| Harvard | Smart Define 2016, unbelievable thesaurus, Smart Define, viewed 26 September, 2026, <https://smartdefine.org/unbelievable/thesaurus/narrower>. |
| MLA | Smart Define. "unbelievable thesaurus" 30 March 2016. Web. 26 September 2026. <https://smartdefine.org/unbelievable/thesaurus/narrower> |