| APA | Smart Define. (2015). toughness thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/toughness/thesaurus/broader |
| Chicago | Smart Define. 2015. "toughness thesaurus" https://smartdefine.org/toughness/thesaurus/broader (accessed September 23, 2026). |
| Harvard | Smart Define 2015, toughness thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/toughness/thesaurus/broader>. |
| MLA | Smart Define. "toughness thesaurus" 21 December 2015. Web. 23 September 2026. <https://smartdefine.org/toughness/thesaurus/broader> |