| APA | Smart Define. (1970). physical ecosystem thesaurus. Retrieved September 21, 2026, from https://smartdefine.org/physical_ecosystem/thesaurus/broader |
| Chicago | Smart Define. 1970. "physical ecosystem thesaurus" https://smartdefine.org/physical_ecosystem/thesaurus/broader (accessed September 21, 2026). |
| Harvard | Smart Define 1970, physical ecosystem thesaurus, Smart Define, viewed 21 September, 2026, <https://smartdefine.org/physical_ecosystem/thesaurus/broader>. |
| MLA | Smart Define. "physical ecosystem thesaurus" 1 January 1970. Web. 21 September 2026. <https://smartdefine.org/physical_ecosystem/thesaurus/broader> |