As far as I know this only works for 360: So the quickest way of getting to the area is to head from winterhold and go towards the shrine of azura, a notable landmark is the sightless pit, it is directly above it. It is at an old burial site, you will know it by 3 skeletons you have to kill, so go ahead and kill them. The glitch is with one of the skeletons, it will be the one on the table with the conjuration spellbook "Doors of Oblivion" above his head,if possible you should try to keep the skeleton on the table (so you dont have to search for his bones) then go to his inventory and then back out, then go back in, when you do there should be a copy of the book on him. Just repeat this process to your liking, he never runs out. You can sell the books at the College of Winterhold, and at any random merchant. I dont know if the patch has corrected this or not , so I suppose it is a wait-and-see process.