Khazar University Mathematics Department professor Nazim Karimov's article entitled "On the spectral properties of high-order differential operators with periodic boundary conditions" was published in "Differential Equations" journal (2023, Vol. 59, No. 3, pp. 312-331). Note that "Differential Equations" magazine is indexed in "Web of Science" and "Scopus" databases.
The present paper deals with the spectral properties of the set of eigenvalues and the system of root functions for the differential operator.
Link to the article: