Reference
Dimitri Kaljof, Antanas Brazauskas, Donatas Kaminskas, Tonu Martma, Petras Musteikis (2004): The Ludfordian carbon isotope excursion in the Vidukle core, Lithuania,
its relations with the Lau Oceanic Event and environmental background in NW Baltica. – Berichte des Institutes für Geologie und Paläontologie der Karl-Franzens-Universität Graz – 8: 60 - 62.