Heibig A, Palade LII. On the existence of solutions to the fractional derivative equations d(alpha)u/dt(alpha)+Au = f, of relevance to diffusion in complex systems. NAMC [Internet]. 2012 Apr. 25 [cited 2025 Jun. 7];17(2):153-68. Available from: https://www.zurnalai.vu.lt/nonlinear-analysis/article/view/14065