| APA | Smart Define. (2011). eugene gladstone o'neill thesaurus. Retrieved September 29, 2026, from https://smartdefine.org/eugene_gladstone_o%27neill/thesaurus/synonyms |
| Chicago | Smart Define. 2011. "eugene gladstone o'neill thesaurus" https://smartdefine.org/eugene_gladstone_o%27neill/thesaurus/synonyms (accessed September 29, 2026). |
| Harvard | Smart Define 2011, eugene gladstone o'neill thesaurus, Smart Define, viewed 29 September, 2026, <https://smartdefine.org/eugene_gladstone_o%27neill/thesaurus/synonyms>. |
| MLA | Smart Define. "eugene gladstone o'neill thesaurus" 26 April 2011. Web. 29 September 2026. <https://smartdefine.org/eugene_gladstone_o%27neill/thesaurus/synonyms> |