Speijer, R.P.; Van Der Zwaan, G.J. 1996. Extinction and survivorship of southern Tethyan benthic foraminifera across the Cretaceous/Palaeogene boundary. In: Hart, M.B. (Editor), Biotic recovery from mass extinction events., pp 343-373. Geological Society Special Publication.
187599
Speijer, R.P.; Van Der Zwaan, G.J. 1996. Extinction and survivorship of southern Tethyan benthic foraminifera across the Cretaceous/Palaeogene boundary. In: Hart, M.B. (Editor), Biotic recovery from mass extinction events., pp 343-373. Geological Society Special Publication.