%0 Journal Article %T On extension of partial orders to total preorders with prescribed symmetric part %A Dmitry V. Akopian %A Valentin V. Gorokhovik %J Mathematics %D 2011 %I arXiv %X For a partial order $\preceq$ on a set X and an equivalency relation S defined on the same set X we derive a necessary and sufficient condition for the existence of such a total preorder on X whose asymmetric part contains the asymmetric part of the given partial order $\preceq$ and whose symmetric part coincides with the given equivalence relation S. This result generalizes the classical Szpilrajn theorem on extension of a partial order to a perfect (linear) order. %U http://arxiv.org/abs/1111.1390v1