[1] GRAY A.:
The volume of a small geodesic ball of s Riemannian manifold. Michigan Math. J. 20 (1973), 329-344.
MR 0339002
[2] GRAY A., VANHECKE L.:
Riemannian geometry as determined by the volume of small geodesic balls. Acta Math. 142 (1979), 157-198.
MR 0521460
[3] KOBAYASHI S., NOMIZU K.:
Foundations of Differential Geometry. Vol.2, New York, Interscience Publ., 1969.
Zbl 0175.48504
[4] RÉDEI L.:
Algebra. Erster Teil, Akademische Verlagsgesellschaft, Geest-Portig K.-G., Leipzig 1959.
MR 0106151
[5] THOMAS T. Y.:
Riemann spaces of class one and their characterization. Acta Math. 67 (1936), 169-211.
MR 1555419 |
Zbl 0015.27304
[6] Van der WAERDEN B. L.: Algebra, Siebte Auflage der Modernen Algebra. Erster Teil, Springer 1966.