Klingenberg, W. (1995). Riemannian geometry (2nd rev. ed.). W. de Gruyter.

Klingenberg, Wilhelm. Riemannian Geometry. 2nd rev. ed. Berlin ; New York: W. de Gruyter, 1995.

Klingenberg, Wilhelm. Riemannian Geometry. 2nd rev. ed. W. de Gruyter, 1995.