1. Agreement between the Russian Federation and the Republic of Kazakhstan on the delimitation of the bottom of the northern part of the Caspian Sea in order to exercise sovereign rights to subsoil use dated 06.07.1998. - URL: https://normativ.kontur.ru/document?moduleId=1&documentId=273085 (date of access: 07/15/2022).
2. Annual Bulletin on the State and Pollution of the Marine Environment of the Russian Sector of the Caspian Sea for 2020 Astrakhan: FSBI “CaspMNIC”. 2021.
3. Caspian Sea: state of the environment (2019). [Electronic resource]. -URL: http://www.caspinfo.net/documents/caspinfo/html_page/poster-caspinfo-final-russian.pdf (accessed 27.07.2022).
4. Convention on the legal status of the Caspian Sea of August 12 (2018). [Electronic resource]. -URL: http://www.kremlin.ru/supplement/5328 (date of access: 07/15/2022).
5. Dubrovina O. (2011). The political mechanism for the implementation of international relations between the regions of states. Power, 10.