6Lubis A M,Kosasih,Basyaruddin.Study of material distribution of four heavy metals(Zn,Cu,P band Co)in rice grain of plants grown along the sides of the main road between Medan and Pematang Siantar(North Sumatra,Indonesia)[J].Bulletin Pertanian(Indonesia),1988,7(2):5-11.
7Ivonin V M,Shumakova G E.Effect of industrial pollution on the condition of road side shelter belts[J].Izvestiya Vysshikh Uchebnykh Zavedenii,Lesnoi Zhurnal,1991,(6):12-17.
8Hamilton R S,Harrison R M.Special issue:highway and urban pollution[J].Sci Total Envir,1996,189-190:1-6.
