The maximum weight stable set problem in $(P_6,\mbox{bull})$-free graphs
  We present a polynomial-time algorithm that finds a maximum weight stable set in a graph that does not contain as an induced subgraph an induced path on six vertices or a bull (the graph with vertices $a, b, c, d, e$ and edges $ab, bc, cd, be, ce$). 
Fr\'ed\'eric Maffray and Lucas Pastor
math.CO cs.DM