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N.  Diane, Hilger, H. H., and Gottschling, M., ?Transfer cells in the seeds of Boraginales?, Botanical Journal of the Linnean Society, vol. 140, no. 2, pp. 155 - 164, 2002.

H. H.  Hilger, Gottschling, M., Selvi, F., Bigazzi, M., Långström, E., Zippel, E., Diane, N., and Weigend, M., ?The Euro+Med treatment of Boraginaceae in Willdenowia 34 ? a response?, Willdenowia, vol. 35, pp. 43 - 48, 2005.

M.  Gottschling, Diane, N., Hilger, H. H., and Weigend, M., ?Testing hypotheses on disjunctions present in the Primarily Woody Boraginales: Ehretiaceae, Cordiaceae, and Heliotropiaceae, inferred from ITS1 sequence data?, International Journal of Plant Sciences, vol. 165, no. 4 SUPPL., pp. S123-S135 - S123-S135, 2004.

N.  Diane, Jacob, C., and Hilger, H. H., ?Leaf anatomy and foliar trichomes in Heliotropiaceae and their systematic relevance?, Flora, vol. 198, no. 6, pp. 468 - 485, 2003.

H. H.  Hilger and Diane, N., ?A systematic analysis of Heliotropiaceae (Boraginales) based on trnL and ITS1 sequence data?, Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie, vol. 125, pp. 19 - 51, 2003.

N.  Diane, Förther, H., and Hilger, H. H., ?A systematic analysis of Heliotropium, Tournefortia, and allied taxa of the Heliotropiaceae (Boraginales) based on ITS1 sequences and morphological data?, American Journal of Botany, vol. 89, no. 2, pp. 287 - 295, 2002.