After a long time, I worked a bit on the library. Since I try to read some information from an existing PDF, I found it very clumsy to access pages. Therefore, I implemented #pageAt: anInteger. In order to test this I had to be able to create arbitrary page trees (see 7.7.3 Page Tree in the spec - like directories and files where the items are ordered). So I added #addPageTree: aPageTree with which you can create any page tree structure you like. These two methods facilitate applications for manipulating PDF files (Extract, Split, Merge etc.). I added examples for extracting and splitting (PDF.Document class #demo12_copyPagesToNewPDF and #demo13_splitPDF). Happy hacking, Christian