Wei-Zhi Wu Ju-Sheng Mi An Interpretation of Belief Functions on Infinite Universes in the Theory of Rough Sets. 71-80 2008 RSCTC http://dx.doi.org/10.1007/978-3-540-88425-5_8 conf/rsctc/2008 db/conf/rsctc/rsctc2008.html#WuM08