This week's book giveaway is in the OCMJEA forum. We're giving away four copies of OCM Java EE 6 Enterprise Architect Exam Guide and have Paul Allen & Joseph Bambara on-line! See this thread for details.
I added the double quotes to make the code neater. This should send you back 1 page in history. If you want to go back 2 or more just supply the number of pages back inside the back function call (i.e. back(5) for 5 pages back).