| APA | Smart Define. (1970). sixteen valve thesaurus. Retrieved October 1, 2026, from https://smartdefine.org/sixteen_valve/thesaurus/synonyms |
| Chicago | Smart Define. 1970. "sixteen valve thesaurus" https://smartdefine.org/sixteen_valve/thesaurus/synonyms (accessed October 1, 2026). |
| Harvard | Smart Define 1970, sixteen valve thesaurus, Smart Define, viewed 1 October, 2026, <https://smartdefine.org/sixteen_valve/thesaurus/synonyms>. |
| MLA | Smart Define. "sixteen valve thesaurus" 1 January 1970. Web. 1 October 2026. <https://smartdefine.org/sixteen_valve/thesaurus/synonyms> |