@article{1183532827,
author = {Nakai, M. and Sario, L.},
title = {Biharmonic classification of Riemannian manifolds},
journal = {Bull. Amer. Math. Soc.},
volume = {77},
number = {6},
year = {1971},
pages = { 432-436},
language = {en},
url = {http://dml.mathdoc.fr/item/1183532827}
}
Nakai, M.; Sario, L. Biharmonic classification of Riemannian manifolds. Bull. Amer. Math. Soc., Tome 77 (1971) no. 6, pp. 432-436. http://gdmltest.u-ga.fr/item/1183532827/