Karimov Shakhobiddin Tuychiboyevich, and Saliyeva Robiykhan Abdukhalil qizi. “Variational Method of Solving Fractional Differential Equation Problems”. Eurasian Journal of Physics,Chemistry and Mathematics, vol. 12, Nov. 2022, pp. 122-6, https://geniusjournals.org/index.php/ejpcm/article/view/2714.