NYAMORADI, Nemat. Existence of multiple positive solutions for quasilinear elliptic systems involving critical hardy–sobolev exponents and sign-changing weight function. Mathematical Modelling and Analysis, [S. l.], v. 17, n. 3, p. 330–350, 2012. DOI: 10.3846/13926292.2012.685956. Disponível em: https://journals.vilniustech.lt/index.php/MMA/article/view/4876. Acesso em: 16 jun. 2025.