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2. Martin. Beginning in the third century CE, references to tea seem more credible, in particular those dating to the time of Hua To, a highly respected physician and surgeon. 29
3. Weinberg BA, Bonnie KB. The World of Caffeine: The Science and Culture of the World’s Most Popular Drug. The Portuguese traders and the Portuguese Jesuit priests, who like Jesuits of every nation busied themselves with the affairs of caffeine, wrote frequently and favorably to compatriots in Europe about tea. Psychology Press; 2001. p. 63. ISBN: 978-0-415-92722-2
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