Averaging Techniques in The Oscillations of Nonlinear Differential Equations With Alternating Coefficients. BSJ [انترنت]. 5 نوفمبر، 2023 [وثق 9 ديسمبر، 2025];(14):227-1. موجود في: https://elc2.su.edu.ly/index.php/bayan/article/view/1838