T. B. Mikenas, A. A. Tregubov, V. A. Zakharov, L. G. Echevskaya, and M. A. Matsko, “Titanium-magnesium catalysts for olefin polymerization - effect of titanium oxidation state on catalyst performance”, p, vol. 53, no. 5, pp. 353–357, Aug. 2022.