| APA | Smart Define. (2015). space travel thesaurus. Retrieved September 30, 2026, from https://smartdefine.org/space_travel/thesaurus/related |
| Chicago | Smart Define. 2015. "space travel thesaurus" https://smartdefine.org/space_travel/thesaurus/related (accessed September 30, 2026). |
| Harvard | Smart Define 2015, space travel thesaurus, Smart Define, viewed 30 September, 2026, <https://smartdefine.org/space_travel/thesaurus/related>. |
| MLA | Smart Define. "space travel thesaurus" 14 April 2015. Web. 30 September 2026. <https://smartdefine.org/space_travel/thesaurus/related> |