Miquel Ferrer Ernest Valveny Francesc Serratosa Horst Bunke Exact Median Graph Computation Via Graph Embedding. 15-24 2008 SSPR/SPR http://dx.doi.org/10.1007/978-3-540-89689-0_6 conf/sspr/2008 db/conf/sspr/sspr2008.html#FerrerVSB08