Huawen Liu Jigui Sun Huijie Zhang Interpretation of Extended Pawlak Flow Graphs Using Granular Computing. 93-115 2008 8 T. Rough Sets http://dx.doi.org/10.1007/978-3-540-85064-9_6 journals/trs/2008-8 db/journals/trs/trs8.html#LiuSZ08