[1] BRAVERMAN E. M.-MEERKOV S. M.-PYATNITSKH E. S.: Conditions for applicability of the method of harmonic balance for systems with hysteresis nonlinearity (in the case of filter hypothesis). Automаt. Remote Control 37 (1976), 1640-1650. MR 0439320 | Zbl 0354.93029

[2] DEIMLING K.: Multivalued Differential Equations. W. De Gruyter, Berlin, 1992. MR 1189795 | Zbl 0820.34009

[3] FEČKAN M.: Bifurcation of periodic solutions in differential inclusions. Appl. Mаth. 42 (1997), 369-393. MR 1467555 | Zbl 0903.34036

[4] HARTMAN P.: Ordinary Differential Equations. Wiley, New York, 1964. MR 0171038 | Zbl 0125.32102

[5] MACKI J. W.-NISTRI P.-ZECCA P.: Mathematical models for hysteresis. SIAM Rev. 35 (1993), 94-123. MR 1207799 | Zbl 0771.34018

[6] MACKI J. W.-NISTRI P.-ZECCA P.: Periodic oscillations in systems with hysteresis. Rocky Mountаin J. Mаth. 22 (1992), 669-681. MR 1180729 | Zbl 0759.34013

[7] MILLER R. K.-MICHEL A. N.: Sinusoidal input-periodic response in nonlinear differential equations containing discontinuous elements. In: Proc. Conf. in Integrаl аnd Functionаl Differentiаl Equаtions. Lecture Notes Pure Appl. Mаth. 67, Springer-Verlаg, New York, 1980. MR 0617042