| APA | Smart Define. (2013). vowel sound thesaurus. Retrieved October 1, 2026, from https://smartdefine.org/vowel_sound/thesaurus/related |
| Chicago | Smart Define. 2013. "vowel sound thesaurus" https://smartdefine.org/vowel_sound/thesaurus/related (accessed October 1, 2026). |
| Harvard | Smart Define 2013, vowel sound thesaurus, Smart Define, viewed 1 October, 2026, <https://smartdefine.org/vowel_sound/thesaurus/related>. |
| MLA | Smart Define. "vowel sound thesaurus" 28 June 2013. Web. 1 October 2026. <https://smartdefine.org/vowel_sound/thesaurus/related> |