Ellis, G. F. R., and MacCallum, M. A. H. (1969).Commun. Math. Phys.,12, 108.
MacCallum, M. A. H. (1973). ?Cosmological Models from a Geometric Point of View,? inCargèse Lectures in Physics, vol. 6. Lectures at the International Summer School of Physics, Cargèse, Corsica, 1971, Ed. E. Schatzman (Gordon and Breach, New York).
Ellis, G. F. R. (1967).J. Math. Phys.,8, 1171.
Stewart, J. M., and Ellis, G. F. R. (1968).J. Math. Phys.,9, 1072.
Wilkinson, D. A. (1979). ?On Exact, Perfect Fluid Solutions of the Einstein Field Equations,? Ph.D. thesis, University of Windsor (unpublished).
Glass, E. N. (1977).J. Math. Phys.,18, 708.
Stephani, H. (1967).Commun. Math. Phys.,5, 337.
Canuto, V., Datta, B., and Kalman, G. (1978).Astrophys. J.,221, 274.
Canuto, V. (1978).Riv. Nuovo Cimento,1, 1.
Jacobs, K. C. (1968).Astrophys. J.,153, 661.
Collins, C. B. (1971).Commun. Math. Phys.,23, 137.
Collins, C. B. (1977).Phys. Lett.,60A, 397.
Damião Soares, I., and Assad, M. J. D. (1978).Phys. Lett.,66A, 359.