Dairbayeva, G. M., and L. N. Temirbekova. “Numerical Analogue of the Gelfand-Levitan on a Finite Interval”. Journal of Mathematics, Mechanics and Computer Science 76, no. 1 (March 23, 2013): 60–70. Accessed December 22, 2024. https://bm.kaznu.kz/index.php/kaznu/article/view/88.