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Diane, N., H. H.  Hilger, and M.  Gottschling. 2002. ?Transfer cells in the seeds of Boraginales?. Bot. J. Linn. Soc. 140:155?164.

Diane, N., C.  Jacob, and H. H.  Hilger. 2003. ?Leaf anatomy and foliar trichomes in Heliotropiaceae and their systematic relevance?. Flora 198:468?485.

Hilger, H. H., and N.  Diane. 2003. ?A systematic analysis of Heliotropiaceae (Boraginales) based on trnL and ITS1 sequence data?. Bot. Jahrb. Syst. 125:19?51.