Mingyan Zhao Ajith Abraham Crina Grosan Hongbo Liu A Fuzzy Particle Swarm Approach to Multiobjective Quadratic Assignment Problems. 516-521 2008 Asia International Conference on Modelling and Simulation http://doi.ieeecomputersociety.org/10.1109/AMS.2008.169 conf/asiams/2008 db/conf/asiams/ams2008.html#ZhaoAGL08