1. Early Silurian inadunate crinoids (Brassfield Formation, Ohio);AUSICH;Journal of Paleontology,1986
2. The Early Paleozoic Bryozoa of the Baltic Provinces;BASSLER;United States National Museum, Bulletin,1911
3. The Kuckers Stage of the Ordovician rocks of NE Estonia;BEKKER;Acta et Commentationes Universitatis Dorpatensis,1921