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William Travis Hanes; Frank Sanello (2004). Opium Wars: The Addiction of One Empire and the Corruption of Another. Sourcebooks, Inc. pp.78–. ISBN 978-1-4022-0149-3. Anderson, Stuart; Berridge, Virginia (2000). "Opium In 20th-Century Britain: Pharmacists, Regulation And The People". Addiction. 95 (1): 23–36. doi: 10.1046/j.1360-0443.2000.951234.x. PMID 10723823. Opium Factories of Bihar – Bihargatha". Bihargatha.in. Archived from the original on September 10, 2011 . Retrieved October 7, 2011. Inglis, Lucy, Milk of Paradise: A History of Opium, Pan Macmillan, London, 2018. **Review: Julie Peakman: "Not Just Smelling the Flowers", History Today History Today Vol. 68/10, October 2018, pp.102–103.The opium trade under the Chinese Communist Party was important to its finances in the 1940s. [82] Peter Vladimirov's diary provided a first hand account. [83] Chen Yung-fa provided a detailed historical account of how the opium trade was essential to the economy of Yan'an during this period. [84] Mitsubishi and Mitsui were involved in the opium trade during the Japanese occupation of China. [85] Office of the Commissioner. "Legislation – Controlled Substances Act". Fda.gov . Retrieved January 25, 2017. Latimer, Dean, and Jeff Goldberg with an Introduction by William Burroughs. Flowers in the Blood: The Story of Opium. New York: Franklin Watts, 1981 For the illegal drug trade, the morphine is extracted from the opium latex, reducing the bulk weight by 88%. It is then converted to heroin which is almost twice as potent, [6] and increases the value by a similar factor. The reduced weight and bulk make it easier to smuggle. The earliest clear description of the use of opium as a recreational drug in China came from Xu Boling, who wrote in 1483 that opium was "mainly used to aid masculinity, strengthen sperm and regain vigor", and that it "enhances the art of alchemists, sex and court ladies". He also described an expedition sent by the Ming dynasty Chenghua Emperor in 1483 to procure opium for a price "equal to that of gold" in Hainan, Fujian, Zhejiang, Sichuan and Shaanxi, where it is close to the western lands of Xiyu. A century later, Li Shizhen listed standard medical uses of opium in his renowned Compendium of Materia Medica (1578), but also wrote that "lay people use it for the art of sex," in particular the ability to "arrest seminal emission". This association of opium with sex continued in China until the end of the 19th century.