1.- The autonomy of European Union law and its own system of "sources of law". 2.- The original law of the European Union. 3.- Legal acts adopted by the institutions of the Union. 4.- International law in the European Union's legal system. 5.- Relations of hierarchy.
Bou Franch, V. (2023). Tema 6: Las fuentes del Derecho de la Unión Europea, (5ª ed.).
https://roderic.uv.es/handle/10550/76855 Tema 6: Las fuentes del Derecho de la Unión Europea, 4ª ed.
