| APA | Smart Define. (1970). Trethowan's sign thesaurus. Retrieved October 1, 2026, from https://smartdefine.org/trethowan%27s_sign/thesaurus/related |
| Chicago | Smart Define. 1970. "Trethowan's sign thesaurus" https://smartdefine.org/trethowan%27s_sign/thesaurus/related (accessed October 1, 2026). |
| Harvard | Smart Define 1970, Trethowan's sign thesaurus, Smart Define, viewed 1 October, 2026, <https://smartdefine.org/trethowan%27s_sign/thesaurus/related>. |
| MLA | Smart Define. "Trethowan's sign thesaurus" 1 January 1970. Web. 1 October 2026. <https://smartdefine.org/trethowan%27s_sign/thesaurus/related> |