1. United Nations, Department of Economic and Social Affairs, Sustainable Development
https://sdgs.un.org/goals
2. Global Indicator Framework for the Sustainable Development Goals and Targets of the 2030 Agenda for Sustainable Development, Version E/CN.3/2022/2,2022
3. Caring for Wildlife: The World Zoo and Aquarium Animal Welfare Strategy;Mellor,2015
4. Offspring survival changes over generations of captive breeding
5. The World Zoo and Aquarium Conservation Strategy. Zoos’ Print
https://www.waza.org/wp-content/uploads/2019/03/WAZA-Conservation-Strategy-2015_Portrait.pdf