an oriented perfect path double cover (oppdc) of a graph $g$ is a collection of directed paths in the symmetric orientation $g_s$ of $g$ such that each arc of $g_s$ lies in exactly one of the paths and each vertex of $g$ appears just once as a beginning and just once as an end of a path. maxov{'a} and ne{v{s}}et{v{r}}il (discrete math. 276 (2004) 287-294) conjectured that ...
