| APA | Smart Define. (2011). heron's bill thesaurus. Retrieved September 29, 2026, from https://smartdefine.org/heron%27s_bill/thesaurus/narrower |
| Chicago | Smart Define. 2011. "heron's bill thesaurus" https://smartdefine.org/heron%27s_bill/thesaurus/narrower (accessed September 29, 2026). |
| Harvard | Smart Define 2011, heron's bill thesaurus, Smart Define, viewed 29 September, 2026, <https://smartdefine.org/heron%27s_bill/thesaurus/narrower>. |
| MLA | Smart Define. "heron's bill thesaurus" 26 April 2011. Web. 29 September 2026. <https://smartdefine.org/heron%27s_bill/thesaurus/narrower> |