| APA | Smart Define. (2015). in operation thesaurus. Retrieved September 24, 2026, from https://smartdefine.org/in_operation/thesaurus/antonyms |
| Chicago | Smart Define. 2015. "in operation thesaurus" https://smartdefine.org/in_operation/thesaurus/antonyms (accessed September 24, 2026). |
| Harvard | Smart Define 2015, in operation thesaurus, Smart Define, viewed 24 September, 2026, <https://smartdefine.org/in_operation/thesaurus/antonyms>. |
| MLA | Smart Define. "in operation thesaurus" 13 April 2015. Web. 24 September 2026. <https://smartdefine.org/in_operation/thesaurus/antonyms> |