Remarks on Zasada efektywności w prawie międzynarodowym [Principle of effectiveness in international law] by Janusz Symonides: On the Anniversary of the Conclusion of the Polish-German Treaties of 1950, 1970 and 1990. Polish Yearbook of International Law, [S. l.], v. 40, p. 23–38, 2021. DOI: 10.24425/pyil.2021.138427. Disponível em: https://czasopisma.inp.pan.pl/index.php/pyil/article/view/2746. Acesso em: 13 mar. 2026.