“Towards a Theoretical Background for Strong-Scattering Inversion – Direct Envelope Inversion and Gel’fand-Levitan-Marchenko Theory”. Communications in Computational Physics 28, no. 1 (June 5, 2020): 41–73. Accessed December 6, 2025. https://global-sci.com/index.php/cicp/article/view/6829.