Katharina Hahn Joos-Hendrik Böse Birgitta König-Ries Philipp Obreiter Robust and fair trading in volatile environments: overcoming technical problems and uncooperativeness. 33-40 2007 conf/mobide/2007 MobiDE http://doi.acm.org/10.1145/1254850.1254857 db/conf/mobide/mobide2007.html#HahnBKO07