7W J chamberlain,O T Chortyk.Effects of curing and fertilization on nitrosamines formation in bright and burley tobacco.Beitrage Zur Tabakforschung International,1992,15(2):72-76.
8Burton H R,Bush L P,Djordjevic M V.Influence of temperture and Humidity on the accumulation of tobacco-specific nitrosamines in stored burlev tobacco.J.Agric Food Chem,1989,37:1372-1377.
9M u rthy,K S N,et al.Studies on the leaf chem istry and quality of agency burley tobacco,Tob.Res,1989,15(2):124-131.
10Harold R.Burton,George H Childs,Roger A.Andersen et al.Changes in chem icai composition of burley tobacco during senescence and curing.Tobacco-specific nitrosam ines.J.Agric Food Chem,1989,37:426-430.