Kubyshkin, V.A., and S.S. Postnov. “The Optimal Control Problem for Linear Systems of Non-Integer Order With Lumped and Distributed Parameters”. Discontinuity, Nonlinearity, and Complexity, vol. 4, no. 4, Aug. 2026, pp. 429-43, https://doi.org/10.5890/DNC.2015.11.006.