Nova Acta Physico-Medica Academiae Caesareae Leopoldino-Carolinae Naturae Curiosorum Exhibentia Ephemerides sive Observationes Historias et Experimenta… Band 16, Nummer 1, 1832, S. 325, Tafel 17 (online).
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Les Cactées. Histoire, Patrie Organes de Vegetation, Inflorescence Culture etc. Paris 1868, S. 35 (online).