1. Azmy, K., Veizer, J., Bassett, M.G. &Copper, P. (1998): Oxygen and carbon isotopic composition of Silurian brachiopods: Implications for coeval seawater and glaciations.—Geol. Soc. Amer. Bull.,110, 1499–1512
2. Bassett, M.G., Kaljo, D. &Teller, L. (1989): The Baltic region.— Nat. Mus. Wales, Geol. Ser.,9, 158–170
3. Bickert, T., Pätzold, J., Samtleben, C. &Munnecke, A. (1997): Paleoenvironmental changes in the Silurian indicated by stable isotopes in brachiopod shells from Gotland, Sweden.— Geochimica et Cosmochimica Acta61, 2717–2730
4. Bickert, T. &Wefer, G. (1999): South Atlantic and benthic formanifer δ13C - deviations: Implications for reconstructing the Late Quaternary deep-water circulation.—Deep-Sea Res.,46, 137–452
5. Brenchley, P. J. (1988): Environmental changes close to the Ordivician-Silurian boundary.—In:Cocks, L.R.M. & Rickards R.B. (eds.), A global Analysis of the Ordovician-Silurian Boundary.—Brit. Mus. (Nat. Hist.) Bull,43 (Geol. Ser.), 177–385