Kasim Abbas Hussain, Waleed Jamal Hasan. “Solving Oscillatory Problems Using Trigonometrically-Fitting Improved Runge-Kutta Nystrom Method”. Mathematical Statistician and Engineering Applications, vol. 71, no. 4, Oct. 2022, pp. 5419-27, doi:10.17762/msea.v71i4.1130.