T. . Vlakhov, G. Hadjichristov, Y. Marinov, and N. Scaramuzza, “Ion Conductivity of Nanocomposite Solid Polymer Electrolyte PEO-PVP-NaIO4 with Added TiO2 Nanoparticles”, C. R. Acad. Bulg. Sci., vol. 75, no. 3, pp. 349–357, Mar. 2022.