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Müller-Wille, Staffan. "Characters Written with Invisible Ink: Elements of Hybridism 1751 - 1875 / Staffan Müller-Wille." Conference A Cultural History of Heredity II : 18th and 19th Centuries.(2003) .

Müller-Wille, Staffan. "Characters Written with Invisible Ink: Elements of Hybridism 1751 - 1875 / Staffan Müller-Wille." Conference A Cultural History of Heredity II : 18th and 19th Centuries.(2003), .