Okwara, E. C., and V. C. Wakwe. “Serum Levels of Selenium and Manganese in the Elderly in Owerri Metropolis: https://doi.Org/10.60787/NMJ-64-1-233”. Nigerian Medical Journal, vol. 64, no. 1, May 2023, p. 129, doi:10.60787/nmj.v64i1.233.