USDA, ARS, National Genetic Resources Program. Germplasm Resources Information Network. (GRIN) [Online Database]. National Germplasm Resources Laboratory, Beltsville, Maryland. [1]Archivado el 15 de enero de 2009 en Wayback Machine. (6 jul 2008)
USDA, ARS, National Genetic Resources Program. Germplasm Resources Information Network. (GRIN) [Online Database]. National Germplasm Resources Laboratory, Beltsville, Maryland. [1]Archivado el 15 de enero de 2009 en Wayback Machine. (6 jul 2008)