"2000 Years of Parallel Societies in Stone Age Central Europe." Ruth Bollongino, Olaf Nehlich, Michael P. Richards, Jörg Orschiedt, Mark G. Thomas, Christian Sell, Zuzana Fajkošová, Adam Powell, Joachim Burger. Science. Published Online October 10, 2013. DOI: 10.1126/science.1245049 https://www.science.org/doi/10.1126/science.1245049