Hufnagel, H. "The fine quality of uttering undeniable truth": William Crookes und seine "Researches in the Phenomena of Spiritualism" / Henning Hufnagel. Dynamiken des Wissens.(2007).
Lua i Stíl Chicago (17ú heag.)Hufnagel, Henning. ""The Fine Quality of Uttering Undeniable Truth": William Crookes Und Seine "Researches in the Phenomena of Spiritualism" / Henning Hufnagel." Dynamiken Des Wissens.(2007) .
Lua MLA (8ú heag.)Hufnagel, Henning. ""The Fine Quality of Uttering Undeniable Truth": William Crookes Und Seine "Researches in the Phenomena of Spiritualism" / Henning Hufnagel." Dynamiken Des Wissens.(2007), .
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