Do you mean audit history? One method would be similar to the following sample that you could extend to create a PDF from the data returned:
BUT the method used above via JCR Query is an implementation detail. For future proofing, you should use the ReplicationStatus status = page.adaptTo(ReplicationStatus.class in your code to get the audit logs for a particular page, rather than a straight JCR query. (recommended by Jörg Hoh @ http://forums.adobe.com/message/5253760).