@article{oai:repository.dl.itc.u-tokyo.ac.jp:00040294,
 author = {Kuhnel, W.},
 issue = {3},
 journal = {Journal of mathematical sciences, the University of Tokyo},
 month = {},
 note = {application/pdf},
 pages = {649--662},
 title = {Essential Conformal Fields in Pseudo-Riemannian Geometry. II},
 volume = {4},
 year = {1997}
}