| APA | Smart Define. (2015). vernal equinox thesaurus. Retrieved September 29, 2026, from https://smartdefine.org/vernal_equinox/thesaurus/narrower |
| Chicago | Smart Define. 2015. "vernal equinox thesaurus" https://smartdefine.org/vernal_equinox/thesaurus/narrower (accessed September 29, 2026). |
| Harvard | Smart Define 2015, vernal equinox thesaurus, Smart Define, viewed 29 September, 2026, <https://smartdefine.org/vernal_equinox/thesaurus/narrower>. |
| MLA | Smart Define. "vernal equinox thesaurus" 13 April 2015. Web. 29 September 2026. <https://smartdefine.org/vernal_equinox/thesaurus/narrower> |