Шегда, Л. М. (2019). NECESSARY CONDITION FOR THE EXISTENCE OF SOLUTIONS OF A WEAKLY NONLINEAR BOUNDARY-VALUE PROBLEM WITH IMPULSIVE ACTION. PRECARPATHIAN BULLETIN OF THE SHEVCHENKO SCIENTIFIC SOCIETY. Number, (1(25), 40–44. Retrieved from https://pvntsh.nung.edu.ua/index.php/number/article/view/203