A web-fed rotary printing press (1) for alternatively printing, in a perfecting mode, a single web (10) or, in a non-perfecting mode, first and second webs (6, 8), comprises a first impression cylinder (16) having a plurality of first blanket cylinders (22a, 22b, 22c, 22d) and a corresponding plurality...http://www.google.com.au/patents/US6745688?utm_source=gb-gplus-sharePatent US6745688 - Lithographic web-fed rotary printing press
