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Notre connaissance de l'histoire de la pollution de l'atmosphere de notre planete par le plomb doit beaucoup a l'etude de ce metal dans les archives que constituent les neiges et glaces deposees au Groenland et en Antarctique. Cette etude est pourtant particulierement difficile, par suite de l'extraordinaire purete des neiges et glaces polaires. Des mesures fiables n'ont pu etre realisees, sous l'impulsion...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.