| APA | Smart Define. (2013). lighter-than-air thesaurus. Retrieved October 1, 2026, from https://smartdefine.org/lighter-than-air/thesaurus/antonyms |
| Chicago | Smart Define. 2013. "lighter-than-air thesaurus" https://smartdefine.org/lighter-than-air/thesaurus/antonyms (accessed October 1, 2026). |
| Harvard | Smart Define 2013, lighter-than-air thesaurus, Smart Define, viewed 1 October, 2026, <https://smartdefine.org/lighter-than-air/thesaurus/antonyms>. |
| MLA | Smart Define. "lighter-than-air thesaurus" 28 June 2013. Web. 1 October 2026. <https://smartdefine.org/lighter-than-air/thesaurus/antonyms> |