Peter Korosec Jurij Silc Klemen Oblak Franc Kosel The differential ant-stigmergy algorithm: an experimental evaluation and a real-world application. 157-164 2007 IEEE Congress on Evolutionary Computation http://dx.doi.org/10.1109/CEC.2007.4424467 conf/cec/2007 db/conf/cec/cec2007.html#KorosecSOK07