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Becker, Bless & Brauckmann | 
1984 | 
Hasselbachtal, the section best displaying the Devonian-Carboniferous boundary beds in the Rhenish Massif (Rheinisches Schiefergebirge).	 
Courier Forschungsinstitut Senckenberg, 67: 181-191, fig.1-6, pl.1; Frankfurt a.M.	 
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