Grigg D. The worlds of tea and coffee: patterns of consumption. GeoJournal 2002; 57: 283-94.
James JE. Understanding caffeine: a biobehavioral analysis. Thousand Oaks (CA): Sage Publications; 1997.
Nawrot P, Jordan S, Eastwood J, Rotstein J, Hugenholtz A, Feeley M. Effects of caffeine on human health. Food Addit Contam 2003; 20: 1-30.
Moss SE, Klein R, Klein BE. Prevalence of and risk factors for dry eye syndrome. Arch Ophthalmol 2000; 118: 1264-8.
Osei KA, Ovenseri-Ogbomo G, Kyei S, Ntodie M. The effect of caffeine on tear secretion. Optom Vis Sci 2014; 91: 171-7.
Amaechi OU, Savia J. The effect of caffeine on tear formation. J Niger Optom Assoc 2005; 12: 14-6.
Arita R, Yanagi Y, Honda N, Maeda S, Maeda K, Kuchiba A, et al. Caffeine increases tear volume depending on polymorphisms within the adenosine A2a receptor gene and cytochrome P450 1A2. Ophthalmology 2012; 119: 972-8.
Kardon RH. Anatomy and physiology of the autonomic nervous system. In:Miller NR, Newman NJ, Walsh FB, Hoyt WF, eds. Walsh & Hoyt's clinical neuro-ophthalmology. 6th ed. Philadelphia (PA): Lippincott Williams & Wilkins; 2005.
Pholpramool C. Secretory effect of prostaglandins on the rabbit lacrimal gland in vivo. Prostaglandins Med 1979; 3: 185-92.
Pholpramool C, Tangkrisanavinont V. Evidence for the requirement of sympathetic activity in the PGE1-induced lacrimal secretion in rabbits. Arch Int Pharmacodyn Ther 1983; 265: 128-37.
Gilbard JP, Rossi SR, Heyda KG, Dartt DA. Stimulation of tear secretion and treatment of dry-eye disease with 3-isobutyl-1-methylxanthine. Arch Ophthalmol 1991; 109: 672-6.
Nettleton JA, Follis JL, Schabath MB. Coffee intake, smoking, and pulmonary function in the Atherosclerosis Risk in Communities Study. Am J Epidemiol 2009; 169: 1445-53.
McCarty CA, Bansal AK, Livingston PM, Stanislavsky YL, Taylor HR. The epidemiology of dry eye in Melbourne, Australia. Ophthalmology 1998; 105: 1114-9.
Schein OD, Tielsch JM, Munõz B, Bandeen-Roche K, West S. Relation between signs and symptoms of dry eye in the elderly: a population-based perspective. Ophthalmology 1997; 104: 1395-401.