KNAUFF, M. Strategic substitutes and complements in cournot oligopoly with product differentiation. Metody Ilościowe w Badaniach Ekonomicznych, [S. l.], v. 11, n. 1, p. 199–211, 2010. Disponível em: https://qme.sggw.edu.pl/article/view/3061. Acesso em: 21 lis. 2024.