<Name>, Shadowfang Keep holds a book, the Book of Ur, which would be much prized in my collection. Ur was a great mage of Dalaran before the coming of the Scourge, his studies in other worlds are of much value to... certain parties among the Forsaken.
Enter Shadowfang Keep and find the book. Bring it to me, and I will report your service to our Dark Lady...
Did you find the book, <name>?
Very good. This book will add nicely to my collections of the workings of Ur. His knowledge was great, but his conscience held him from true power. And so when the Scourge came and his strength was tested, it failed.
We of the Forsaken cannot afford such weakness, if we are to survive...
...If we are to conquer.
- The book is in the room with Fenrus. It's a large blue book on the left bookshelf as you enter the room.