Article

Bergström, S.M., Chen, X., Gutiérrez-Marco, J.C. & Dronov, A. 2009. The new chronostratigraphic classification of the Ordovician System and its relations to major regional series and stages and to δ13C chemostratigraphy. Lethaia 42 (1), Mar 2009: 97-107. [Online: 16 Oct 2008] ≡