I'd been browsing the web looking for digital books to replace the physical ones I own when I came across the Project Management Institute's (or PMI for short) Guide to the Project Management Body of Knowledge (or PMBOK) 4th edition as a PDF.
If you are already a PMI member you can download a free version of the PMBOK Guide 4th by logging into PMI's website, go to the members area, select the resources tab and click on the global library.
If you're not a PMI member you can probably find the PMBOK guide on Rapidshare or the thePirateBay.org. Just search for PMBOK.
This is an excellent project management book to have as a reference. So if you like it, purchase it.
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