Valentina Casola Antonino Mazzeo Nicola Mazzocca Massimiliano Rak An Innovative Policy-Based Cross Certification Methodology for Public Key Infrastructures. 100-117 2005 conf/europki/2005 EuroPKI http://dx.doi.org/10.1007/11533733_7 db/conf/europki/europki2005.html#CasolaMMR05