| APA | Smart Define. (1970). i regret to say thesaurus. Retrieved September 28, 2026, from https://smartdefine.org/i_regret_to_say/thesaurus/synonyms |
| Chicago | Smart Define. 1970. "i regret to say thesaurus" https://smartdefine.org/i_regret_to_say/thesaurus/synonyms (accessed September 28, 2026). |
| Harvard | Smart Define 1970, i regret to say thesaurus, Smart Define, viewed 28 September, 2026, <https://smartdefine.org/i_regret_to_say/thesaurus/synonyms>. |
| MLA | Smart Define. "i regret to say thesaurus" 1 January 1970. Web. 28 September 2026. <https://smartdefine.org/i_regret_to_say/thesaurus/synonyms> |