Rulon, L. ., Robertson, J. ., Lovell, M. ., Deibel, M. ., Ehmann, W. ., & Markesber, W. . (1969). Serum zinc levels and Alzheimer’s disease. Biological Trace Element Research, 75(1-3), 79-85. https://doi.org/10.1385/bter:75:1-3:79 (Original work published 1969)