Vladimir E. Alekseev Vadim V. Lozin Dmitriy Malyshev Martin Milanic The Maximum Independent Set Problem in Planar Graphs. 96-107 2008 MFCS http://dx.doi.org/10.1007/978-3-540-85238-4_7 conf/mfcs/2008 db/conf/mfcs/mfcs2008.html#AlekseevLMM08