VALKOV, Vladimir. THE ROLE OF SOCIAL FACTORS IN ECONOMIC DEVELOPMENT AT REGIONAL LEVEL IN BULGARIA. KNOWLEDGE - International Journal , [S. l.], v. 66, n. 1, p. 49–52, 2024. Disponível em: http://ojs.ikm.mk/index.php/kij/article/view/6989. Acesso em: 28 aug. 2026.