Lyudmil Aleksandrov Hristo Djidjev Hua Guo Anil Maheshwari Partitioning Planar Graphs with Costs and Weights. 98-110 2002 conf/alenex/2002 ALENEX http://link.springer.de/link/service/series/0558/bibs/2409/24090098.htm db/conf/alenex/alenex2002.html#AleksandrovDGM02