1. L. M. Silverman, ?Inversion of multivariable linear systems,? IEEE Trans. Automat. Control AC,14, No. 3, 270?276 (1969).
2. R. M. Hirschorn, ?Invertibility of nonlinear control systems,? SIAM J. Control. Optim.,17, No. 2, 289?297 (1979).
3. A. M. Kovalev, Nonlinear Control and Observation Problem in the Theory of Dynamical Systems [in Russian], Naukova Dumka, Kiev (1980).
4. A. M. Kovalev and V. F. Shcherbak, ?Conditions for the identifiability of nonlinear mechanical systems,? Mekh. Tverd. Tela,16, 77?91 (1984).
5. V. F. Shcherbak, ?Identifiability of mechanical systems with unknown initial state,? Mekh. Tverd. Tela,17, 83?87 (1985).