Peters JM. Factors Affecting Caffeine Toxicity: A Review of the Literature. The Journal of Clinical Pharmacology and the Journal of New Drugs, 1967, s. 131–141. Dostupné online. DOI: 10.1002/j.1552-4604.1967.tb00034.x.
fda.gov
FDA Consumer Advice on Powdered Pure Caffeine [online]. . Dostupné online.
Peters JM. Factors Affecting Caffeine Toxicity: A Review of the Literature. The Journal of Clinical Pharmacology and the Journal of New Drugs, 1967, s. 131–141. Dostupné online. DOI: 10.1002/j.1552-4604.1967.tb00034.x.
web.archive.org
MedlinePlus Drug Information: Caffeine (Systemic) [online]. nlm.nih.gov, [cit. 2018-09-26]. Dostupné online. Archivované 2007-02-23 z originálu.
WEISS, Luke M.; KEARNS, James K.. Caffeine and theobromine analysis of Paullinia yoco, a vine harvested by indigenous peoples of the upper Amazon [online]. . Dostupné online.