[1] J. P. LaSalle: The time optimal control problem. Contributions to the Theory of Nonlinear Oscillations, 5 (1960), 1-24. MR 0145169 | Zbl 0095.29503

[2] J. Kurzweil Z. Vorel: On linear control systems. Bul. Inst. Pol. Iasi, s.n., t. VI (X) (1960), 13-20 (MR 25 1357, J. P. LaSalle). MR 0137909

[3] E. B. Lee L. Markus: Foundations of Optimal Control Theory. J. Wiley & Sons, 1964. MR 0220537

[4] A. M. Formaľskii: Determination of the control region for an unstable linear system. (Russian). Izv. AN SSSR, Teor. Kib. 5 (1965), 129-136. MR 0205717

[5] R. F. Brammer: Controllability in linear autonomous systems with positive controllers. SIAM J. Control, 10 (1972), 339-353. MR 0304003 | Zbl 0253.93008

[6] S. H. Saperstone: Global controllability of linear systems with positive controls. SIAM J. Control II (1973), 417-423. MR 0325194 | Zbl 0259.93003

[7] V. I. Korobov A. P. Marinic E. N. Podoľskii: Controllability of a linear autonomous system with constraints on the control. (Russian). Diff. Uravn. II (1975), 1967-1979. MR 0399999

[8] L. A. Kun, Yu. F. Pronosin: Global controllability of linear systems. (Russian). Avt. i Telem. 3 (1972), 155-156; Engl, transl.: Autom, Remote Control 33 (1972), 456-457. MR 0408915

[9] L. A. Kun: Connection between local and global controllability. (Russian). Avt. i Telem. 10 (1977), 12-15; Engl, transl.: Autom. Remote Control 38 (1977), 1437-1439. MR 0490132 | Zbl 0423.93011

[10] Nguyen Khoa Son: Global controllability of linear autonomous systems: geometric consideration. Systems and Control Letters, 6 (1985), 207-212. MR 0801872

[11] R. M. Bianchini Tiberio: Local controllability, rest states and cyclic points. SIAM J. C. O. 21 (1983), 714-720. MR 0710996

[Q] R. Conti: Processi di controllo lineari in Rn. „Quaderni dell'Unione Matematica Italiana" 30, Pitagora Ed., Bologna, 1985.