Da-kuan Wei and Xian-zhong Zhou and Dong-jun Xin and Zhi-wei Chen, Variable Rough Set Model and Its Knowledge Reduction for Incomplete and Fuzzy Decision Information Systems. journal = {International Journal of Computer and Information Engineering}, [online]. World Academy of Science, Engineering and Technology. June 2007, vol. 6(6). 1642 - 1646 [viewed 19 April 2024]. Available from: https://publications.waset.org/pdf/10310.