1. Hartle, J. B., and Sharp, D. (1966)Astrophys. J.,147, 317.
2. Bardeen, J. M. (1973). Rapidly rotating stars, disks and black holes, inBlack Holes. Les Astres Occlus. Gordon and Breach, New York.
3. Wahlquist, H. D., and Estabrook, F. B. (1966). (unpublished)
4. Harrison, B. K. (1970).Phys. Rev. D.,1, 2269.
5. Carter, B. (1969).J. Math. Phys.,10, 70.