A strip of multi-part business forms includes a plurality of primary sheets and secondary sheet each attached to a primary sheet. The primary sheets are separated by and folded along lines of weakening formed in the strip. Each secondary sheet is removable from a primary sheet to reveal a die cut...http://www.google.de/patents/US5782691?utm_source=gb-gplus-sharePatent US5782691 - Mailable multi-sheet business form for prevention of tenting during printing 
