PDFedit is free and open source library for manipulating PDF documents, released under terms of GNU GPL version 2.
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PDF Mod is a simple application for modifying PDF documents.
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PDFCreator is one of the best known programs to create PDF files from any application.
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pdftohtml is a utility which converts PDF files into HTML and XML formats.
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PDF Split and Merge is an easy to use tool to merge and split pdf documents.
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