Marco Dorigo Mauro Birattari Christian Blum Luca Maria Gambardella Francesco Mondada Thomas Stützle Ant Colony Optimization and Swarm Intelligence, 4th International Workshop, ANTS 2004, Brussels, Belgium, September 5 - 8, 2004, Proceedings 3172 3-540-22672-9 ANTS Workshop Lecture Notes in Computer Science Springer 2004 db/conf/antsw/antsw2004.html