Salvador Romaguera E. A. Sánchez-Pérez Oscar Valero The Dual Complexity Space as the Dual of a Normed Cone. 165-174 2006 161 Electr. Notes Theor. Comput. Sci. http://dx.doi.org/10.1016/j.entcs.2006.04.031 db/journals/entcs/entcs161.html#RomagueraSV06