| APA | Smart Define. (2011). once in a blue moon thesaurus. Retrieved September 29, 2026, from https://smartdefine.org/once_in_a_blue_moon/thesaurus/broader |
| Chicago | Smart Define. 2011. "once in a blue moon thesaurus" https://smartdefine.org/once_in_a_blue_moon/thesaurus/broader (accessed September 29, 2026). |
| Harvard | Smart Define 2011, once in a blue moon thesaurus, Smart Define, viewed 29 September, 2026, <https://smartdefine.org/once_in_a_blue_moon/thesaurus/broader>. |
| MLA | Smart Define. "once in a blue moon thesaurus" 24 May 2011. Web. 29 September 2026. <https://smartdefine.org/once_in_a_blue_moon/thesaurus/broader> |