Daughter of Time, by Josephine Tey. Excellent book. Makes the case that Richard III was maligned.The lady did not think highly of the Tudors. Oh, and the Princes' bones were found in a staircase in the Tower, not in Greenwich.
One of my favorite books. I don't believe that the bones found at the Tower were ever examined for DNA. Were they the Princes? Probably, but it still doesn't answer the question: Who was responsible for their deaths? I believe that Henry VII had more to gain from the deaths of his brothers-in-law than Richard had.
Actually, I've read that the bones were found under the ground during some demolition and laying of new foundations, and may be much more ancient. :')