Gaber, T. J., V. L. Dingerkus, M. J. Crockett, S. Bubenzer-Busch, K. Helmbold, C. L. Sánchez, B. Dahmen, B. Herpertz-Dahlmann, and F. D. Zepf. “Studying the Effects of Dietary Body Weight-Adjusted Acute Tryptophan Depletion on Punishment-Related Behavioral Inhibition”. Food & Nutrition Research, vol. 59, Aug. 2015, doi:10.3402/fnr.v59.28443.