Cefn Hoile Fang Wang Erwin Bonsma Paul Marrow Core specification and experiments in DIET: a decentralised ecosystem-inspired mobile agent system. 623-630 2002 conf/atal/2002 AAMAS http://doi.acm.org/10.1145/544862.544890 db/conf/atal/aamas2002.html#HoileWBM02