Uniqueness and non-existence of metrics with prescribed Ricci curvature
Annales de l'I.H.P. Analyse non linéaire, Volume 1 (1984) no. 5, p. 351-359 
@article{AIHPC_1984__1_5_351_0,
     author = {DeTurck, Dennis and Koiso, Norihito},
     title = {Uniqueness and non-existence of metrics with prescribed Ricci curvature},
     journal = {Annales de l'I.H.P. Analyse non lin\'eaire},
     publisher = {Gauthier-Villars},
     volume = {1},
     number = {5},
     year = {1984},
     pages = {351-359},
     zbl = {0556.53026},
     mrnumber = {779873},
     language = {en},
     url = {http://www.numdam.org/item/AIHPC_1984__1_5_351_0}
}

Deturck, Dennis M.; Koiso, Norihito. Uniqueness and non-existence of metrics with prescribed Ricci curvature. Annales de l'I.H.P. Analyse non linéaire, Volume 1 (1984) no. 5, pp. 351-359. http://www.numdam.org/item/AIHPC_1984__1_5_351_0/

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