Matthias F. M. Stallmann Franc Brglez Debabrata Ghosh Heuristics and Experimental Design for Bigraph Crossing Number Minimization. 74-93 http://link.springer.de/link/service/series/0558/bibs/1619/16190074.htm 1999 conf/alenex/1999 ALENEX db/conf/alenex/alenex1999.html#StallmannBG99