Evidence for shallow-water 'Upper Kellwasser' anoxia in the Frasnian-Famennian reefs of Alberta, Canada Bond, David P. G. ; Zatoń, Michał ; Wignall, Paul B. ; Marynowski, Leszek Abstract Publication: Lethaia Pub Date: July 2013 DOI: 10.1111/let.12014 Bibcode: 2013Letha..46..355B