Subsequent biotic crises delayed marine recovery following the late Permian mass extinction event in northern Italy Foster, William J. ; Danise, Silvia ; Price, Gregory D. ; Twitchett, Richard J. Abstract Publication: PLoS ONE Pub Date: March 2017 DOI: 10.1371/journal.pone.0172321 Bibcode: 2017PLoSO..1272321F