
https://carnegieendowment.org/files/2-24_Lehne-EU_Geopolitics.pdf

https://www.chba.org.uk/for-members/library/overseas-seminars/the-status-of-gibraltar-under-eu-law

https://www.otto-brenner-stiftung.de/fileadmin/user_data/stiftung/Aktuelles/AH93/AH_93_Haller_Web.pdf