| APA | Smart Define. (2013). into the future thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/into_the_future/thesaurus/antonyms |
| Chicago | Smart Define. 2013. "into the future thesaurus" https://smartdefine.org/into_the_future/thesaurus/antonyms (accessed September 21, 2026). |
| Harvard | Smart Define 2013, into the future thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/into_the_future/thesaurus/antonyms>. |
| MLA | Smart Define. "into the future thesaurus" 17 May 2013. Web. 21 September 2026. <https://smartdefine.org/into_the_future/thesaurus/antonyms> |