Sandu, G., and T. Tanninen. “THE BIRTH OF MODAL LOGIC IN NORTHERN EUROPE”. Bulletin of Taras Shevchenko National University of Kyiv. Philosophy 2, no. 2 (June 27, 2017): 9-19. Accessed July 11, 2026. https://bulletinphilosophy-knu.kyiv.ua/index.php/journal/article/view/9.