Pilar Fernandez-Ferreiros Maria de los Angeles Gomez-Molleda Laureano González-Vega Partial solvability by radicals. 84-91 2002 conf/issac/2002 ISSAC http://doi.acm.org/10.1145/780506.780517 db/conf/issac/issac2002.html#Fernandez-FerreirosGG02