| APA | Smart Define. (2013). rare species of penguin thesaurus. Retrieved October 1, 2026, from https://smartdefine.org/rare_species_of_penguin/thesaurus/synonyms |
| Chicago | Smart Define. 2013. "rare species of penguin thesaurus" https://smartdefine.org/rare_species_of_penguin/thesaurus/synonyms (accessed October 1, 2026). |
| Harvard | Smart Define 2013, rare species of penguin thesaurus, Smart Define, viewed 1 October, 2026, <https://smartdefine.org/rare_species_of_penguin/thesaurus/synonyms>. |
| MLA | Smart Define. "rare species of penguin thesaurus" 18 May 2013. Web. 1 October 2026. <https://smartdefine.org/rare_species_of_penguin/thesaurus/synonyms> |