[1] C. Atkinson A. F. S. Mitchell: Rao's distance measure. Preprint of the Imperial College of Science and Technology, London 1972.

[2] D. M. Bates D. G. Watts: Relative curvature measures of nonlinearity. J. Roy. Statist. Soc. B42 (1980), 1-25. MR 0567196

[3] E. M. L. Beale: Confidence regions in non-linear estimation. J. Roy. Statist. Soc. B 22 (1960), 41-88. MR 0119289 | Zbl 0096.13201

[4] E. A. Coddington N. Levinson: Theory of Ordinary Differential Equations. McGraw-Hill Comp., New York 1955. MR 0069338

[5] J. Milnor: Morse Theory. Princeton Univ. Press, Princeton, N. J. 1963. MR 0163331 | Zbl 0108.10401

[6] C. R. Rao: On the distance between two populations. Sankhya 9 (1949), 246-248. MR 0031695

[7] S. Sternberg: Lectures on Differential Geometry. Second printing. Prentice-Hall, Englewood Cliffs 1965. MR 0193578