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Thomas and Olga de Hartmann - http://en.wikipedia.org/wiki/Thomas_and_Olga_de_Hartmann
Wikipedia's very short biography of the Thomas and Olga de Hartmann |
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Jeanne de Salzmann - http://en.wikipedia.org/wiki/Jeanne_de_Salzmann
Wikipedia's biography of her life. |
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Fritz Peters - http://www.fritzpeters.info/
Dedicated to Fritz Peters (1913-1979), he is most well known for his memoirs covering his early years living at G. I. Gurdjieff's Institute for the Harmonious Development of Man. |
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The Thomas de Hartmann Papers - http://webtext.library.yale.edu/xml2html/music/ht-d.htm
Documents de Hartmann's life and work through musical sketches, manuscript scores, and printed music and contains materials relating to G.I. Gurdjieff. |