H. Shakouri Mohammad Bagher Menhaj A single fuzzy rule to smooth the sharpness of mixed data: Time and frequency domains analysis. 2446-2465 2008 159 Fuzzy Sets and Systems 18 http://dx.doi.org/10.1016/j.fss.2008.01.019 db/journals/fss/fss159.html#ShakouriM08