Parameterized Eulerian Strong Component Arc Deletion Problem on   Tournaments
  In the problem {\sc Min-DESC}, we are given a digraph $D$ and an integer $k$, and asked if there exists a set $A'$ of at most $k$ arcs in $D$, such that if we remove the arcs of $A'$, in the resulting digraph every strong component is Eulerian. {\sc Min-DESC} is NP-hard; Cechl\'{a}rov\'{a} and Schlotter (IPEC 2010) asked if the problem is fixed-parameter tractable when parameterized by $k$. We consider the subproblem of{\sc Min-DESC} when $D$ is a tournament. We show that this problem is fixed-parameter tractable with respect to $k$. 
Robert Crowston, Gregory Gutin, Mark Jones and Anders Yeo
cs.DS cs.CC