no. 1
Spinorial solution associated to a radially symmetric radiation field in general relativity
Annales de l'I.H.P. Physique théorique, Tome 16 (1972) no. 1, pp. 29-39. 
@article{AIHPA_1972__16_1_29_0,
     author = {Oliveira, Colber and Arbex, Nazira},
     title = {Spinorial solution associated to a radially symmetric radiation field in general relativity},
     journal = {Annales de l'I.H.P. Physique th\'eorique},
     pages = {29--39},
     publisher = {Gauthier-Villars},
     volume = {16},
     number = {1},
     year = {1972},
     zbl = {0228.53028},
     language = {en},
     url = {archive.numdam.org/item/AIHPA_1972__16_1_29_0/}
}
Oliveira, Colber G.; Arbex, Nazira. Spinorial solution associated to a radially symmetric radiation field in general relativity. Annales de l'I.H.P. Physique théorique, Tome 16 (1972) no. 1, pp. 29-39. http://archive.numdam.org/item/AIHPA_1972__16_1_29_0/

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