| APA | Smart Define. (2015). diphthong thesaurus. Retrieved September 23, 2026, from https://smartdefine.org/diphthong/thesaurus/related |
| Chicago | Smart Define. 2015. "diphthong thesaurus" https://smartdefine.org/diphthong/thesaurus/related (accessed September 23, 2026). |
| Harvard | Smart Define 2015, diphthong thesaurus, Smart Define, viewed 23 September, 2026, <https://smartdefine.org/diphthong/thesaurus/related>. |
| MLA | Smart Define. "diphthong thesaurus" 10 April 2015. Web. 23 September 2026. <https://smartdefine.org/diphthong/thesaurus/related> |