Mahmood, S., K. Hamad, kareem‎., and A. Shex. “Solution of Multi-Order Fractional Differential Equation Based on Conformable Derivative by Shifted Legendre Polynomial”. Cihan University-Erbil Scientific Journal, Vol. 5, no. 2, Dec. 2021, pp. 64-68, doi:10.24086/cuesj.v5n2y2021.pp64-68.