"I dreamed of a winged wolf bound to earth with grey stone chains," he said. "It was a green dream, so I knew it was true. A crow was trying to peck through the chains, but the stone was too hard and his beak could only chip at them."
"Did the crow have three eyes?"
On the next page, Jojen makes it clear that Bran is the chained winged wolf. He believes the three-eyed crow sent him to Winterfell to break the chains, which he interprets to be Bran's inability to open his third eye.