| APA | Smart Define. (1970). tinbergen's four questions thesaurus. Retrieved September 29, 2026, from https://smartdefine.org/tinbergen%27s_four_questions/thesaurus/broader |
| Chicago | Smart Define. 1970. "tinbergen's four questions thesaurus" https://smartdefine.org/tinbergen%27s_four_questions/thesaurus/broader (accessed September 29, 2026). |
| Harvard | Smart Define 1970, tinbergen's four questions thesaurus, Smart Define, viewed 29 September, 2026, <https://smartdefine.org/tinbergen%27s_four_questions/thesaurus/broader>. |
| MLA | Smart Define. "tinbergen's four questions thesaurus" 1 January 1970. Web. 29 September 2026. <https://smartdefine.org/tinbergen%27s_four_questions/thesaurus/broader> |