Não informado. (1839). Memoirs of the Geological Survey of the United Kingdon. Institute of Geological Sciences.
Chicago-referens (17:e uppl.)Não informado. Memoirs of the Geological Survey of the United Kingdon. London: Institute of Geological Sciences, 1839.
MLA-referens (8:e uppl.)Não informado. Memoirs of the Geological Survey of the United Kingdon. Institute of Geological Sciences, 1839.
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