Abdollah Homaifar Marwan Bikdash C. Clifton Approximating an optimal feedback control law by a generalized Sugeno controller. 39-57 2001 121 Fuzzy Sets and Systems 1 http://dx.doi.org/10.1016/S0165-0114(99)00171-2 db/journals/fss/fss121.html#HomaifarBC01