| APA | Smart Define. (1970). period of pro thesaurus. Retrieved September 22, 2026, from https://smartdefine.org/period_of_pro/thesaurus/broader |
| Chicago | Smart Define. 1970. "period of pro thesaurus" https://smartdefine.org/period_of_pro/thesaurus/broader (accessed September 22, 2026). |
| Harvard | Smart Define 1970, period of pro thesaurus, Smart Define, viewed 22 September, 2026, <https://smartdefine.org/period_of_pro/thesaurus/broader>. |
| MLA | Smart Define. "period of pro thesaurus" 1 January 1970. Web. 22 September 2026. <https://smartdefine.org/period_of_pro/thesaurus/broader> |