A. Afrouzi, Ghasem, Samad Mohseni Kolagar, Armin Hadjian, and Jiafa Xu. 2018. “Variational Approach for a Class of Two-Point Fractional Boundary Value Systems”. MATEMATIKA 34 (2):351-64. https://doi.org/10.11113/matematika.v34.n2.898.