• [1] V. F. Butuzov, Asymptotic formulae for solutions of systems of differential equations with small parameter at the derivative in the semi-infinite interval, Vestnik Moscov. Univ. 4 (1963), 3-14. (Russian) MR 0153932 (27:3893)
• [2] E. A. Coddington and N. Levinson, Theory of ordinary differential equations, McGraw-Hill, New York, 1955. MR 0069338 (16:1022b)
• [3] L. Flatto and N. Levinson, Periodic solutions of singularly perturbed systems, J. Rational Mech. Anal. 4 (1955), 943-950. MR 0076126 (17:849h)
• [4] K. O. Friedrichs and W. Wasow, Singular perturbations of non-linear oscillations, Duke Math. J. 13 1946), 367-381. MR 0018308 (8:272d)
• [5] J. J. Levin and N. Levinson, Singular perturbations of non-linear systems of differential equations and associated boundary layer equation, J. Rational Mech. Anal. 3 (1954), 247-270. MR 0061241 (15:795f)
• [6] W. Hahn, On the general concept of stability and Liapunov's direct method, Technical Rep. No. 485, U.S. Army Mathematics Research Center, Madison, Wisconsin, 1964.
• [7] J. L. Massera, On Liapunov's conditions of stability, Ann. of Math. 50 (1949), 705-721. MR 0035354 (11:721f)
• [8] A. N. Tihonov, Systems of differential equations containing a small parameter multiplying the derivative, Mat. Sb. N. S. (31) 73 (1952), 575-585. (Russian) MR 0055515 (14:1085d)

Bibliography

[1]

V. F. Butuzov, Asymptotic formulae for solutions of systems of differential equations with small parameter at the derivative in the semi-infinite interval, Vestnik Moscov. Univ. 4 (1963), 3-14. (Russian) MR 0153932 (27:3893)

[2]

E. A. Coddington and N. Levinson, Theory of ordinary differential equations, McGraw-Hill, New York, 1955. MR 0069338 (16:1022b)

[3]

L. Flatto and N. Levinson, Periodic solutions of singularly perturbed systems, J. Rational Mech. Anal. 4 (1955), 943-950. MR 0076126 (17:849h)

[4]

K. O. Friedrichs and W. Wasow, Singular perturbations of non-linear oscillations, Duke Math. J. 13 1946), 367-381. MR 0018308 (8:272d)

[5]

J. J. Levin and N. Levinson, Singular perturbations of non-linear systems of differential equations and associated boundary layer equation, J. Rational Mech. Anal. 3 (1954), 247-270. MR 0061241 (15:795f)

[6]

W. Hahn, On the general concept of stability and Liapunov's direct method, Technical Rep. No. 485, U.S. Army Mathematics Research Center, Madison, Wisconsin, 1964.

[7]

J. L. Massera, On Liapunov's conditions of stability, Ann. of Math. 50 (1949), 705-721. MR 0035354 (11:721f)

[8]

A. N. Tihonov, Systems of differential equations containing a small parameter multiplying the derivative, Mat. Sb. N. S. (31) 73 (1952), 575-585. (Russian) MR 0055515 (14:1085d)