Instability of Gravitating Object Under Expansion-free Condition in Rastall Theory. Punjab University Journal of Mathematics, [S. l.], v. 55, n. 6, p. 222–240, 2023. Disponível em: https://pujm.pu.edu.pk/index.php/pujm/article/view/183. Acesso em: 29 jun. 2025.