## Summary

The concept of a resonance set is used to state and prove sufficient conditions for the existence of a periodic solution of the nonlinear vector differential equation f(D)x + + BMg(D)x=p, in which D=d/dt and the functions M, p are periodic in the t variable.

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## Additional information

Entrata in Redazione il 19 giugno 1976.

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### Cite this article

Smith, R.A. Resonance sets of the feedback control equation.
*Annali di Matematica* **114, **195–205 (1977). https://doi.org/10.1007/BF02413786

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### Keywords

- Differential Equation
- Periodic Solution
- Feedback Control
- Control Equation
- Nonlinear Vector