Korzhevskii, D. E., O. V. Kirik, V. V. Guselnikova, D. L. Tsyba, E. A. . Fedorova, and I. P. Grigorev. “Changes in Cytoplasmic and Extracellular Neuromelanin in Human Substantia Nigra With Normal Aging”. European Journal of Histochemistry, vol. 65, no. s1, Sept. 2021, doi:10.4081/ejh.2021.3283.