KRIKOS, Constantinos. Definition of mass and production of equations of general relativity. Open Science Journal, [S. l.], v. 5, n. 3, 2020. DOI: 10.23954/osj.v5i3.2543. Disponível em: https://osjournal.org/ojs/index.php/OSJ/article/view/2543. Acesso em: 9 sep. 2025.