NANIEWICZ, Zdzisław; NOCKOWSKA, Magdalena. On variational approach to economic equilibrium — type problem. Annales Mathematicae Silesianae, [S. l.], v. 20, p. 57–71, 2006. Disponível em: https://journals.us.edu.pl/index.php/AMSIL/article/view/14068. Acesso em: 12 apr. 2025.