R. Ruffini & S. Bonazzola (1969). «Systems of Self-Gravitating Particles in General Relativity and the Concept of an Equation of State». Physical Review187 (5): 1767-1783. Bibcode:1969PhRv..187.1767R. doi:10.1103/PhysRev.187.1767.
R. Ruffini & S. Bonazzola (1969). «Systems of Self-Gravitating Particles in General Relativity and the Concept of an Equation of State». Physical Review187 (5): 1767-1783. Bibcode:1969PhRv..187.1767R. doi:10.1103/PhysRev.187.1767.