Spectral gaps of the periodic Schrödinger operator when its potential is an entire function. - Plamen Djakov; Boris Mityagin (Adv. Appl. Math., 2003)

Simple and double eigenvalues of the Hill operator with a two-term potential. - Plamen Djakov; Boris Mityagin (J. Approx. Theory, 2005)

Trace formula and Spectral Riemann Surfaces for a class of tri-diagonal matrices. - Plamen Djakov; Boris Mityagin (J. Approx. Theory, 2006)

Equiconvergence of spectral decompositions of 1D Dirac operators with regular boundary conditions. - Plamen Djakov; Boris Mityagin (J. Approx. Theory, 2012)

Asymptotics of spectral gaps of 1D Dirac operator whose potential is a linear combination of two exponential terms. - Berkay Anahtarci; Plamen Djakov (Asymptot. Anal., 2015)