Reinhard Haupenthal (born 17 February 1945; died 29 September 2016^{[citation needed]}) was a German Esperantist, Volapükist (or Volapükologist), translator, and linguist. Donald J. Harlow described Haupenthal's personal style in a warning to potential readers of Haupenthal's translation of Goethe's Young Werther: "the vocabulary used by Haupenthal is far from standard, and at times the Esperanto verges on the incomprehensible."^[1]

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