Medieval burials in coffins at the area of Tomsk Ob region: a local phenomenon or a "Mongol trace"?

The article tells about medieval burials in wooden coffins at the area of Tomsk Ob region. These graves exclusively date to the 13th-15th centuries and there is no trace of them found in either an earlier or a later time period. This may mean that the ritual of burying the dead in a coffin had been practiced in the region for a relatively short period of time. All in all, there have been identified and described 17 medieval coffin burials. All of them stand out markedly against other graves. They come with a rich and diverse burial inventory (weapons, adornments, rare articles of art, etc.). In half of the cases, they are also accompanied by the burial of horsehide and horse tack. All this leads the author to put forth a hypothesis that the dead buried in the wooden coffins were representatives of the military elite. Such "elite" graves are known to have existed in the 13th-14th centuries across the Altai, Transbaikal, and South Urals regions, where they appeared during the period when the Mongols came into to the area. Coffin graves turning up in other regions are linked to Mongol traditions, which spread wide during the Mongol conquests in the 13th-14th centuries. So it appears that the medieval interments in coffins aren't local phenomenon in the Tomsk Ob region but the sign of "the Mongolian trail" in the history of the Region