1. Yu. P. Zhigalko and S. I. Solov’ev, “Natural oscillations of a beam with a harmonic oscillator,” Russ. Math. 45 (10), 33–35 (2001).
2. S. I. Solov’ev, “Eigenvibrations of a beam with elastically attached load,” Lobachevskii J. Math. 37, 597–609 (2016).
3. S. I. Solov’ev, “Eigenvibrations of a plate with elastically attached load,” Preprint SFB393/03-06 (Tech. Univ. Chemnitz, 2003).
4. S. I. Solov’ev, “Vibrations of plates with masses,” Preprint SFB393/03-18 (Tech. Univ. Chemnitz, 2003).
5. S. I. Solov’ev, Nonlinear Eigenvalue Problems. Approximate Methods (Lambert Academic, Saarbrücken, 2011) [in Russian].