1. D. Aeyels, Generic observability of differentiable systems, preprint, April 1980, Dept. of System Dynamics, State Univ. Gent.
2. R. Bowen, Entropy of group endomorphisms and homogeneous spaces, Trans. A.M.S., 153 (1971), 401–414.
3. Regional Conference Series in Mathematics;R. Bowen,1977
4. Lecture Notes in Mathematics;M. Denker,1976
5. H. Federer, Geometric measure theory, Springer-Verlag, Berlin, 1969.