| APA | Smart Define. (1970). keeping a stiff upper lip thesaurus. Retrieved September 27, 2026, from https://smartdefine.org/keeping_a_stiff_upper_lip/thesaurus/antonyms |
| Chicago | Smart Define. 1970. "keeping a stiff upper lip thesaurus" https://smartdefine.org/keeping_a_stiff_upper_lip/thesaurus/antonyms (accessed September 27, 2026). |
| Harvard | Smart Define 1970, keeping a stiff upper lip thesaurus, Smart Define, viewed 27 September, 2026, <https://smartdefine.org/keeping_a_stiff_upper_lip/thesaurus/antonyms>. |
| MLA | Smart Define. "keeping a stiff upper lip thesaurus" 1 January 1970. Web. 27 September 2026. <https://smartdefine.org/keeping_a_stiff_upper_lip/thesaurus/antonyms> |