"Nicotiana L.". Germplasm Resources Information Network. United States Department of Agriculture. 2006-04-13. Arquivado dende o orixinal o 2010-08-20. Consultado o 2010-06-03.
"Nicotiana L.". Germplasm Resources Information Network. United States Department of Agriculture. 2006-04-13. Arquivado dende o orixinal o 2010-08-20. Consultado o 2010-06-03.