The head of “Differential Equations” department of IMM doct.phys.math.sci.prof. Akper Aliyev was on professional trip at Moscow State University in Moscow from March 28 to April 01, 2015. On March 30, 2015 at the faculty of Calculation Mathematics and Cybernetics of Moscow State University, at the seminar under the guidance of acad. E.I. Moiseev and prof. I.S. Lomov “Spectral theory of differential operators and actual problems of mathematics physics”, prof. Akper Aliyev gave the lecture “Existence of global solutions for semilinear Klein-Gordon system”.