{"id":"001288723","type":"book","title":"X-ray microdensitometry applied to subfossil tree-rings: growth characteristics of ancient pines from the southern boreal forest zone in Finland at intra-annual to centennial time-scales","pages":"675-686","container-title":"Vegetation History and Archaeobotany, 17,6 (2008","author":[{"family":"Helama","given":"S."}],"issued":{"raw":"2008"}}