Eleazar Jiménez Serrano Keijiro Araki Shigeru Kusakabe Enforcing the optimal set of controls for state feedback with non-redundant controllers. 1394-1399 2007 SMC http://dx.doi.org/10.1109/ICSMC.2007.4413734 conf/smc/2007 db/conf/smc/smc2007.html#SerranoAK07