Deng-Feng Li 0001 Yong-Chun Wang Shu Liu Feng Shan Fractional programming methodology for multi-attribute group decision-making using IFS. 219-225 2009 9 Appl. Soft Comput. 1 https://doi.org/10.1016/j.asoc.2008.04.006 db/journals/asc/asc9.html#LiWLS09