Victoria Sherrow. Encyclopedia of hair: a cultural history. Page 149
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Duthe's birth date is given as 1748–1752 in various sources. Duthe's death date is given as 1820, 1830 and 1831 in various sources. This article uses the dates of 1748–1830, as given in the Encyclopedia of Prostitution and Sex Work, Volume 1, by Melissa Hope Ditmore, Greenwood 2006, Page 119.