geol-2012-40-5-395http://www.ipgg.sbras.ru/ru/Files/publications/ibc/geol-2012-40-5-395.pdfgeol-2012-40-5-395publ-the-oldest-evidence-of-bioturbation-on-earth-2012-035033

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publ-the-oldest-evidence-of-bioturbation-on-earth-2012-035033