@article{ref1,
title="A study of the development of tolerance for caffeinated beverages",
journal="Journal of experimental psychology",
year="1933",
author="Winsor, A. L. and Strongin, E. I.",
volume="16",
number="5",
pages="725-734",
abstract="Previous research with parotid secretion had indicated that the normal flow from either of these glands could be measured accurately. Furthermore, a preliminary test had shown that the rate of secretion from these glands was definitely affected by the ingestion of coffee. Normal secretion for fifteen minutes was first recorded, and this served as a control rate. Then the subject drank two cups of coffee and the rate of secretion in the subsequent period was recorded. Warm water and decaffeinated coffee were occasionally substituted. Tests made when both habituated and non-habituated coffee drinkers were used as subjects yielded significant differences between the two groups. Accordingly a new group of unhabituated subjects was selected and each subject was given two pints of a commercialized beverage containing caffeine at a given hour each afternoon. Gradual reduction in parotid flow following the giving of the dosage on successive days was shown. (PsycINFO Database Record (c) 2012 APA, all rights reserved)<p />",
language="",
issn="0022-1015",
doi="10.1037/h0071270",
url="http://dx.doi.org/10.1037/h0071270"
}