Hello Daffodil enthusiast For those interested; The following link contains a paper on all species of narcissi .Happy reading. (Thanks Nancy)
http://daffodilusa.com/references/references.html#research
Ben J.M.Zonneveld Nationaal Herbarium Nederland POBox 9514 2300 RA Leiden, The Netherlands telf 071 5274738 E-mail: 
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