Tianxiao Liu Tuyet-Tram Dang-Ngoc Dominique Laurent Cost Framework for a Heterogeneous Distributed Semi-structured Environment. 1-11 2007 conf/apweb/2007w APWeb/WAIM Workshops http://dx.doi.org/10.1007/978-3-540-72909-9_1 db/conf/apweb/apweb2007w.html#LiuDL07