W Haak, I Lazaridis, N Patterson, N Rohland, S Mallick, B Llamas, G Brandt, S Nordenfelt, E Harney, K Stewardson, Q Fu, A Mittnik, E Bánffy, C Economou, M Francken, S Friederich, RG Pena, F Hallgren, V Khartanovich, A Khokhlov, M Kunst, P Kuznetsov, H Meller, O Mochalov, V Moiseyev, N Nicklisch, SL Pichler, R Risch, MA Rojo Guerra, C Roth, A Szécsényi-Nagy, J Wahl, M Meyer, J Krause, D Brown, D Anthony, A Cooper, KW Alt e D Reich, Massive migration from the steppe was a source for Indo-European languages in Europe., in Nature, vol. 522, n. 7555, 11 giugno 2015, pp. 207–11, Bibcode:2015Natur.522..207H, DOI:10.1038/nature14317, PMC 5048219, PMID 25731166, arXiv:1502.02783.
«We generated genome-wide data from 69 Europeans who lived between 8,000–3,000 years ago by enriching ancient DNA libraries for a target set of almost 400,000 polymorphisms.... This steppe ancestry persisted in all sampled central Europeans until at least 3,000 years ago, and is ubiquitous in present-day Europeans. These results provide support for a steppe origin of at least some of the Indo-European languages of Europe.»