Books with title Ambush at Cisco Swamp

Robert's second adventure finds him in the U.S.—but he's not in the present-day U.S. for long!The Irwins are in Texas, doing some crocodilian research on the American Alligator. Robert knows that the ancient deinosuchus roamed around these parts, and when his fossil transports him back in time, he gets to see first hand the prehistoric predator take on an albertasaurus and win!