On isospectral deformations of riemannian metrics
Compositio Mathematica, Volume 40 (1980) no. 3, p. 319-324 
@article{CM_1980__40_3_319_0,
     author = {Kuwabara, Ruishi},
     title = {On isospectral deformations of riemannian metrics},
     journal = {Compositio Mathematica},
     publisher = {Sijthoff et Noordhoff International Publishers},
     volume = {40},
     number = {3},
     year = {1980},
     pages = {319-324},
     zbl = {0406.53038},
     mrnumber = {571054},
     language = {en},
     url = {http://www.numdam.org/item/CM_1980__40_3_319_0}
}

Kuwabara, Ruishi. On isospectral deformations of riemannian metrics. Compositio Mathematica, Volume 40 (1980) no. 3, pp. 319-324. http://www.numdam.org/item/CM_1980__40_3_319_0/

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