ANTONOVA, D. .; TODOROVA, A. . COMPLEX NATURE OF THE EFFICIENCY OF SOCIAL INVESTMENTS IN BULGARIA. International Conference of Management and Industrial Engineering, [S. l.], v. 11, p. 391–396, 2023. DOI: 10.56177/11icmie2023.57. Disponível em: https://www.icmie.ro/index.php/icmie/article/view/57. Acesso em: 21 oct. 2026.