LINDEN , M.; HELMBOLD , K.; KEMPF , J.; SIPPAS , S.; FILSS , C.; LANGEN , K.-J.; EISERT , A.; ZEPF , F. D. Dietary tryptophan depletion in humans using a simplified two amino acid formula - a pilot study. Food & Nutrition Research, v. 60, 16 Dec. 2016.