| APA | Smart Define. (2011). clyde william tombaugh thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/clyde_william_tombaugh/thesaurus/synonyms |
| Chicago | Smart Define. 2011. "clyde william tombaugh thesaurus" https://smartdefine.org/clyde_william_tombaugh/thesaurus/synonyms (accessed September 22, 2026). |
| Harvard | Smart Define 2011, clyde william tombaugh thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/clyde_william_tombaugh/thesaurus/synonyms>. |
| MLA | Smart Define. "clyde william tombaugh thesaurus" 26 April 2011. Web. 22 September 2026. <https://smartdefine.org/clyde_william_tombaugh/thesaurus/synonyms> |